Reactive trityl derivatives: Stabilised carbocation mass-tags for life sciences applications

Article abstract of DOI:10.1039/b810600b

The rational design of novel triarylmethyl (trityl)-based mass tags (MT) for mass-spectrometric (MS) applications is described. We propose a "pK_R+ rule" to correlate the stability of trityl carbocations with their MS performance: trityls with higher pK_R+ values ionise and desorb better. Trityl blocks were synthesised that have high pK_R+ values and are stable in conditions of MS analysis; these MTs can be ionised by matrix as well as irradiation with a 337 nm nitrogen laser. ¹³C-Labelled tags were prepared for MS quantitation applications. Moreover, the tags were equipped with a variety of functional groups allowing conjugation with different functionalities within (bio)molecules to enhance the MS characteristics of the latter. The MS behaviour of model polycationic trityl compounds with and without the matrix was studied to reveal that poly-trityl clusters are always singly charged under the (MA)LDI-TOF conditions. Several peptide-trityl conjugates were prepared and comparisons revealed a beneficial effect of trityl tags on the conjugate detection in MS. Trityl compounds containing para-methoxy- and dimethylamine groups, as well as a xanthene fragment, showed considerable enhancement in MS detection of model peptides; thus they are promising tools for proteomic applications. Dimethoxytrityl derivatives allow one to distinguish between Arg- and Lys-containing peptides. Maleimido trityl derivatives are suitable for the efficient derivatisation of thiol-containing peptides in pyridine.

Full text of DOI:10.1039/b810600b

Reactive trityl derivatives: stabilised carbocation mass-tags for life
sciences applications
Alexey V. Ustinov, Vadim V. Shmanai, Kaajal Patel, Irina A. Stepanova, Igor A. Prokhorenko,
Irina V. Astakhova, Andrei D. Malakhov, Mikhail V. Skorobogatyi, Pablo L. Bernad, Jr, Safraz
Khan, Mona Shahgholi, Edwin M. Southern, Vladimir A. Korshun,* and Mikhail S. Shchepinov*
Supporting Information
Synthetic procedures for compounds 4a-f, 5a-k, 7a-j, 8, 10f,g,h, 11a,b, 12a-h, 13a,c, 15a,c-h,
16a,b, 17c,d, 18, 19, 20, 21, 22b,c, 23b,d, 24d, 27b, 28d-h, 29, 31, 34, 35, 36, 37, 38, 39, 42, 43,
44, 45, 54, 55, 56:
(Experimental Section)
page 2–33
References
page 34

Experimental Section
1
13
Instrumentation. 500 MHz H and 125.7 MHz C NMR spectra were recorded on a Bruker
DRX-500 spectrometer and referenced to CDCl3 (7.25 ppm) and DMSO-d6 (2.50 ppm). H–13C
1
gradient-selected HMQC and HMBC spectra were obtained by using 2048 (t2)×256 (t1) complex
point data sets, zero filled to 2048 (F2)×1024 (F1) points. The spectral widths were 13 ppm and
1
13
200 ppm for H and C dimensions, respectively. HMBC spectra were measured with 50 ms
delay for evolution of long-range couplings. (MA)LDI-TOF mass spectra were obtained using a
Voyager Elite Biospectrometry Research Station (PerSeptive Biosystems, Vestec Mass
Spectrometry Products) in a positive ion mode. EI-TOF HRMS and ESI-TOF HRMS spectra in
positive ion mode were obtained using Micromass LCT reflection TOF mass spectrometer.
Analytical thin-layer chromatography was performed on the Kieselgel 60 F254 precoated
aluminium plates (Merck), spots were visualised under UV light (254 nm). Column
chromatography was performed on silica gel (Merck Kieselgel 60 0.040–0.063 mm).
Reagents and solvents. Reagents obtained from commercial suppliers were used as received. 4-
Hydroxy-4′-methoxybenzophenone (3),[1] Pd(PPh3)4,[2] tert-butyl 6-bromohexanoate,[3] were
prepared as described. Solvents were mainly HPLC grade and used without further purification
unless otherwise noted. DCM was always used freshly distilled over CaH2. THF was distilled
over powdered LiAlH4 or over sodium benzophenone ketyl and stored over 4Å molecular sieves
under nitrogen. DMF was freshly distilled under reduced pressure.
O
Cl(CH2)3CO2But
MeONa / HMPA
O
75%
O
OH
O
O
4-[3-(tert-Butyloxycarbonyl)propoxy]benzophenone (4a). A solution of sodium methoxide
prepared from sodium (0.46 g, 20 mmol) and MeOH (50 mL), was added to the solution of 4-
hydroxybenzophenone (3.96 g, 20 mmol) in MeOH (100 mL). The mixture was evaporated to
dryness, coevaporated with tert-butanol (2×40 mL), the residue was dissolved in HMPA (30 mL)
and tert-butyl 4-chlorobutyrate (4.0 g, 22 mmol) was added in one portion. The mixture was
heated at 100ºC for 5 h, then cooled, diluted with water (300 mL) and extracted with EtOAc
(2×200 mL). The combined organic layers were washed with water (5×100 mL), dried over
Na2SO4, and evaporated. The residue was chromatographed on silica gel in 1→4% EtOAc in
toluene to give the desired compound as white crystalline solid, mp 72ºC (EtOAc–hexane). Yield
5.10 g (75%). ESI-TOF HRMS: m/z = 341.1752 [M+H]+, calc. for [C21H25O4]+ 341.1747. NMR
(DMSO-d6): 7.73 (d, 2H, J = 8.9 Hz, ArH); 7.70–7.62 (m, 3H, ArH); 7.54 (m, 2H, ArH); 7.07 (d,
2H, J = 8.9 Hz, ArH); 4.09 (t, 2H, J = 6.4 Hz, OCH2); 2.38 (t, 2H, J = 7.3 Hz, COCH2); 1.97 (m,
2H, CH2CH2CH2); 1.40 (s, 9H, CH3).
O
Br(CH2)5CO2But
K2CO3 / Me2CO
O
84%
O
OH
O
O
4-[5-(tert-Butyloxycarbonyl)pentyloxy]benzophenone (4b). To
a
solution of 4-
hydroxybenzophenone (1.98 g, 10.0 mmol) in in dry acetone (80 mL) dry K2CO3 (14 g, 0.1 mol)
and tert-butyl 6-bromohexanoate[4] (3.76 g, 15 mmol) were added, and the mixture was stirred
for 48 h at ambient temperature, then filtered, and the solid was washed with acetone. The
combined filtrate was evaporated, and the residue was dissolved in CHCl3 (100 mL), filtered,
and evaporated. The residue was chromatographed on silica gel in 0→6% EtOAc in toluene to
give desired product (3.10 g, 84%) as a colourless oil. ESI-TOF HRMS: m/z = 369.2051
[M+H]+, calc. for [C23H29O4]+ 369.2060. NMR (DMSO-d6): 7.73 (d, 2H, J = 8.7 Hz, ArH); 7.70–
7.62 (m, 3H, ArH); 7.54 (t, 2H, J = 7.6 Hz, ArH); 7.06 (d, 2H, J = 8.7 Hz, ArH); 4.07 (t, 2H, J =

6.4 Hz, OCH2); 2.21 (t, 2H, J = 7.4 Hz, COCH2); 1.74 (m, 2H), 1.56 (m, 2H), 1.42 (m, 2H)
(OCH2CH2CH2CH2); 1.39 (s, 9H, CH3).
O
Cl(CH2)3CO2But
MeONa / HMPA
O
55%
O
O
HO
OH
O
O
O
O
4,4′-Bis[3-(tert-butyloxycarbonyl)propoxy]benzophenone (4c). 4,4′-Dihydroxybenzophenone
(4.24 g, 20 mmol) was alkylated as described in the procedure for 4a using sodium (1.15 g, 50
mmol) and tert-butyl 4-chlorobutyrate (8.04 g, 45 mmol). The desired compound was purified by
chromatography on silica gel in 2→5% EtOAc in toluene. Yield 5.49 g (55%), white crystalline
solid, mp 92ºC (EtOAc–hexane). ESI-TOF HRMS: m/z = 499.2697 [M+H]+, calc. for
[C29H39O7]+ 499.2690. NMR (DMSO-d6): 7.69 (d, 4H, J = 8.8 Hz, ArH); 7.05 (d, 2H, J = 8.8 Hz,
ArH); 4.08 (t, 4H, J = 6.4 Hz, OCH2); 2.38 (t, 4H, J = 7.3 Hz, COCH2); 1.97 (m, 4H,
CH2CH2CH2); 1.41 (s, 18H, CH3).
O
O
Cl(CH2)3CO2But
MeONa / HMPA
O
HO
O
HO
OH
O
2
4d
MeI / K2CO3 /
acetone
O
O
O
O
O
O
O
MeO
O
O
O
4c
O
4e
4-[3-(tert-Butyloxycarbonyl)propoxy]-4′-methoxybenzophenone
(4e).
4,4’-
Dihydroxybenzophenone (4.24 g, 20 mmol) was alkylated as described in the procedure for 2c
using sodium (1.15 g, 50 mmol) and tert-butyl 4-chlorobutyrate[2] (4.47 g, 25 mmol). The
mixture was chromatographed on silica gel in 2→5→10→15% EtOAc in toluene to give 4,4’-
bis[3-(tert-butyloxycarbonyl)propoxy]benzophenone 4c (1.60 g, 16%) and 4-[3-(tert-
butyloxycarbonyl)propoxy]-4′-hydroxybenzophenone (4d) (3.14 g, 44%) as crystalline solid
mp 122–124.5ºC (EtOAc). ESI-TOF HRMS: m/z = 357.1701 [M+H]+, calc. for [C21H25O5]+
357.1697. NMR (DMSO-d6): 10.30 (br.s, 1H, OH), 7.67 (d, 2H, J = 8.8 Hz, ArH); 7.62 (d, 2H, J
= 8.4 Hz, ArH); 7.04 (d, 2H, J = 8.8 Hz, ArH); 6.88 (d, 2H, J = 8.4 Hz, ArH); 4.08 (t, 2H, J = 6.3
Hz, OCH2); 2.38 (t, 2H, J = 7.3 Hz, COCH2); 2.01–1.93 (m, 2H, CH2CH2CH2); 1.40 (s, 9H,
CH3). The latter compound was dissolved in acetone and methylated with MeI (3 eq) and K2CO3
(7 eq) at ambient temperature for 3 h. The solid was filtered and the solution was evaporated.
The residue was dissolved in chloroform, and the solution was filtered and evaporated to give 4e
(3.18 g, 44% based on starting 4,4’-dihydroxybenzophenone), mp 76–78ºC (EtOAc–hexane).
ESI-TOF HRMS: m/z = 371.1846 [M+H]+, calc. for [C22H27O5]+ 371.1853. NMR (DMSO-d6):
7.74–7.66 (m, 4H, ArH); 7.11–7.03 (m, 4H, ArH); 4.08 (t, 2H, J = 6.3 Hz, COCH2); 3.86 (s, 3H,
OCH3); 2.38 (t, 2H, J = 7.3 Hz, COCH2); 2.02–1.91 (m, 2H, CH2CH2CH2); 1.41 (s, 9H, CH3).
O
Br(CH2)5CO2But
O
K2CO3 / acetone
O
MeO
O
MeO
OH
O
3
4f
O
O
OMe
MeO
O
O
4f'
O

4-[5-(tert-Butyloxycarbonyl)pentyloxy]-4′-methoxybenzophenone (4f). To a solution of 4-
hydroxy-4’-methoxybenzophenone (5.84 g, 25.6 mmol) in in dry acetone (250 mL) dry K2CO3
(17.7 g, 0.128 mol) and tert-butyl 6-bromohexanoate[4] (7.05 g, 28.1 mmol) were added, and the
mixture was stirred for 96 h at ambient temperature, then filtered, and the solid was washed with
acetone. The combined filtrate was evaporated, and the residue was dissolved in CHCl3 (150
mL), filtered, and evaporated. The residue was chromatographed on silica gel in 0→20% EtOAc
in toluene to give the desired product (1.99 g, 19.5%). ESI-TOF HRMS: m/z = 399.2175
[M+H]+, calc. for [C24H31O5]+ 399.2166. NMR (DMSO-d6): 7.70 (m, 4H, ArH); 7.06 (m, 4H,
ArH); 4.06 (t, 2H, J = 6.4 Hz, OCH2); 3.86 (s, 3H, OCH3); 2.21 (t, 2H, J = 7.3 Hz, COCH2); 1.75
(m, 2H), 1.56 (m, 2H), 1.42 (m, 2H) (OCH2CH2CH2CH2); 1.39 (s, 9H, CCH3). 4-Methoxy-4′-[5-
(4-methoxybenzoylphenoxycarbonyl)pentyloxy]benzophenone (4f’) (22%) was isolated as a
side product. NMR (DMSO-d6): 7.78 (m, 8H, ArH); 7.19 (d, 2H, J = 8.2 Hz, ArH); 6.95 (m, 6H,
ArH); 4.07 (t, 2H, J = 6.1 Hz, OCH2); 3.88; 3.87 (2s, 6H, OCH3); 2.64 (t, 2H, J = 7.3 Hz,
COCH2); 1.88 (m, 4H, OCH2CH2CH2CH2); 1.64 (m, 2H, OCH2CH2CH2).
General procedure for preparation of trirylmethanols 5. To a stirred solution of
corresponding benzophenone (4.0 mmol) in dry THF (30 mL) the solution of arylmagnesium
bromide (0.5 or 1.0 M, 5.0 mmol) was added in one portion under Ar, and the mixture was kept
at ambient temperature overnight (monitoring by TLC in EtOAc–toluene 1:9). The reaction was
diluted with water (200 mL) and 5% NaHCO3 (100 mL), and extracted with EtOAc (2×100 mL).
The organic phase was dried over Na2SO4, evaporated, and chromatographed on silica gel in
appropriate solvent system.
S
HO
O
O
O
ArMgBr / THF
5a
NMe2
O
HO
O
O
O
O
4a
O
O
5b
OMe
HO
O
O
O
5c
4-{4-[Hydroxy-(thiophen-2-yl)-phenyl-methyl]phenoxy}butanoic acid, tert-butyl ester (5a)
was prepared from 4-[3-(tert-butyloxycarbonyl)propoxy]benzophenone 4a (1.70 g; 5.0 mmol) in
dry THF (50 mL) and 1.0 M 2-thienylmagnesium bromide (7.5 mL, 7.5 mmol). The title
compound was chromatographed on silica gel in toluene with 1.0% of Et3N; yellowish oil. Yield
1.55 g (72%). ESI-TOF HRMS: m/z = 407.1671 [M–OH]+, calc. for [C25H27O3S]+ 407.1675.
NMR (DMSO-d6): 7.42 (m, 1H, H-5 (thiophene)); 7.33–7.21 (m, 5H, ArH (phenyl)); 7.15 (d,
2H, J = 8.9 Hz, ArH (phenyl)); 6.94 (m, 1H, H-4 (thiophene)); 6.84 (d, 2H, J = 8.9 Hz, ArH
(phenyl)); 6.67–6.62 (m, 2H, H-3 (thiophene), OH); 3.95 (t, 2H, J = 6.3 Hz, OCH2); 2.35 (t, 2H,
J = 7.3 Hz, COCH2); 1.91 (m, 2H, CH2CH2CH2), 1.39 (s, 9H, CCH3).
4-{4-[Hydroxy-(4-dimethylaminophenyl)phenyl-methyl]phenoxy}butanoic acid, tert-butyl
ester (5b) was prepared from 4a (1.36 g; 4.0 mmol) in dry THF (30 mL) and 0.5 M 4-
dimethylaminophenylmagnesium bromide (10.0 mL, 5.0 mmol). The compound was
chromatographed on silica gel in same solvent system to give the desired compound as a pinkish
oil. Yield 1.809 g (98%). ESI-TOF HRMS: m/z = 444.2537 [M–OH]+, calc. for [C29H34NO3]+

444.2533. NMR (DMSO-d6): 7.26 (m, 2H, ArH); 7.19 (m, 3H, ArH); 7.07 (d, 2H, J = 8.8 Hz,
ArH); 6.96 (d, 2H, J = 8.8 Hz, ArH); 6.81 (d, 2H, J = 8.8 Hz, ArH); 6.62 (d, 2H, J = 8.8 Hz,
ArH); 6.02 (s, 1H, OH); 3.94 (t, 2H, J = 6.3 Hz, OCH2); 2.86 (s, 6H, NCH3); 2.35 (t, 2H, J = 7.3
Hz, COCH2); 1.91 (m, 2H, CH2CH2CH2), 1.40 (s, 9H, CCH3).
4-[3-(tert-Butyloxycarbonyl)propoxy]-4′-methoxytritanol (5c) was prepared from 4a
(1.85 g; 5.0 mmol) in dry THF (30 mL) and 1 M phenylmagnesium bromide (7.0 mL, 7.0 mmol).
The crude product was chromatographed on silica gel in 0→5% EtOAc in toluene with 0.5% of
Et3N to give the desired compound as a yellow oil. Yield 1.57 g (70%). ESI-TOF HRMS: m/z =
431.2214 [M–OH]+, calc. for [C28H31O4]+ 431.2217. NMR (DMSO-d6): 7.28 (m, 2H, ArH); 7.20
(m, 3H, ArH); 7.07 (m, 4H, ArH); 6.83 (m, 4H, ArH); 6.20 (s, 1H, OH); 3.94 (t, 2H, J = 6.2 Hz,
OCH2); 3.73 (s, 3H, OCH3); 2.35 (t, 2H, J = 7.2 Hz, COCH2); 1.91 (m, 2H, CH2CH2CH2); 1.40
(s, 9H, CH3).
OMe
O
HO
MeO
MgBr
/ THF
O
O
O
O
O
O
5d
4b
6-{4-[Hydroxy-(4-methoxyphenyl)-phenyl-methyl]phenoxy}hexanoic acid, tert-butyl ester
(5d) was prepared from 4-[5-(tert-butyloxycarbonyl)pentyloxy]benzophenone 4b (1.84 g; 5.0
mmol) in dry THF (30 mL) and 1 M 4-methoxyphenylmagnesium bromide (7.0 mL, 7.0 mmol).
The crude tritanol was chromatographed on silica gel in 0→5% EtOAc in toluene with 0.5% of
Et3N to give the desired compound as a colourless oil. Yield 1.597 g (67%). ESI-TOF HRMS:
m/z = 459.2535 [M–OH]+, calc. for [C30H35O4]+ 459.2530. NMR (DMSO-d6): 7.26 (m, 2H,
ArH); 7.20 (m, 3H, ArH); 7.07 (m, 4H, ArH); 6.83 (m, 4H, ArH); 6.17 (s, 1H, OH); 3.92 (t, 2H,
J = 6.4 Hz, OCH2); 3.73 (s, 3H, OCH3); 2.20 (t, 2H, J = 7.3 Hz, COCH2); 1.70 (m, 2H,
OCH2CH2), 1.54 (m, 2H, COCH2CH2), 1.39 (m, 2H, OCH2CH2CH2); 1.38 (s, 9H, CH3).
S
HO
O
O
O
O
O
O
5e
ArMgBr / THF
NMe2
O
HO
O
O
O
O
O
O
O
O
O
O
4c
O
O
5f
OMe
HO
O
O
O
O
O
O
5g
Thiophen-2-yl-bis{4-[3-(tert-butyloxycarbonyl)propoxy]phenyl}methanol (5e) was prepared
from 4,4′-bis[3-(tert-butyloxycarboxy)propoxy]benzophenone 4c (2.49 g; 5.0 mmol) in dry THF
(50 mL) and 1.0 M 2-thienylmagnesium bromide (7.5 mL, 7.5 mmol). The crude tritanol was
chromatographed on silica gel in toluene with 1.0% of Et3N to give the desired compound as a
violet oil. Yield 2.86 g (98%). ESI-TOF HRMS: m/z = 565.2611 [M–OH]+, calc. for
[C33H41O6S]+ 565.2618. NMR (DMSO-d6): 7.40 (m, 1H, H-5 (thiophene)); 7.15 (d, 4H, J = 8.9
Hz, ArH (phenyl)); 6.93 (m, 1H, H-4 (thiophene)); 6.83 (d, 4H, J = 8.9 Hz, ArH (phenyl)); 6.61
(m, 1H, H-3 (thiophene)); 6.52 (s, 1H, OH); 3.94 (t, 4H, J = 6.3 Hz, OCH2); 2.35 (t, 4H, J = 7.3
Hz, COCH2); 1.91 (m, 4H, CH2CH2CH2), 1.39 (s, 18H, CCH3).

4-Dimethylaminophenyl-bis{4-[3-(tert-butyloxycarbonyl)propoxy]phenyl}methanol (5f) was
prepared from 4c (2.49 g; 5.0 mmol) in dry THF (50 mL) and 0.5 M 4-(N,N-
dimethylamino)phenylmagnesium bromide (15 mL, 7.5 mmol). The tritanol was purified by
chromatography on silica gel in toluene with 5% of EtOAc and 1% of Et3N. Pale violet oil, yield
2.22 g (71%). ESI-TOF HRMS: m/z = 602.3477 [M–OH]+, calc. for [C37H48NO6]+ 602.3476.
NMR (DMSO-d6): 7.06 (d, 4H, J = 8.7 Hz, ArH); 6.94 (d, 2H, J = 8.8 Hz, ArH); 6.80 (d, 4H, J =
8.7 Hz, ArH); 6.61 (d, 2H, J = 8.8 Hz, ArH); 5.91 (br.s, 1H, OH); 3.93 (t, 2H, J = 6.2 Hz,
OCH2); 2.85 (s, 6H, NCH3); 2.34 (t, 4H, J = 7.2 Hz, COCH2); 1.91 (m, 4H, CH2CH2CH2), 1.40
(s, 18H, CCH3).
4-Methoxy-4′,4′′-bis[3-(tert-butyloxycarbonyl)propoxy]triphenylmethanol (5g) was prepared
from 4c (2.49 g; 5.0 mmol) in dry THF (30 mL) and 1 M 4-methoxyphenylmagnesium bromide
(7.0 mL, 7.0 mmol). The tritanol was chromatographed on silica gel in 3→7% EtOAc in toluene
to give the desired compound as a colorless oil. Yield 1.88 g (62%). ESI-TOF HRMS: m/z =
589.3162 [M–OH]+, calc. for [C36H45O7]+ 589.3160. NMR (DMSO-d6): 7.10–7.04 (m, 6H, ArH
(phenyl)); 6.86–6.81 (m, 6H, ArH (phenyl)); 6.07 (s, 1H, OH); 3.93 (m, 4H, OCH2); 3.72 (s, 3H,
OCH3); 2.40–2.30 (m, 4H, COCH2); 1.95-1.85 (m, 4H, CH2CH2CH2), 1.40 (s, 18H, CCH3).
S
HO
O
MeO
O
O
5h
ArMgBr / THF
NMe2
O
HO
O
MeO
O
O
O
O
MeO
4e
O
5i
OMe
HO
O
O
MeO
O
5j
4-{4-[Hydroxy-(thiophen-2-yl)-(4-methoxyphenyl)-methyl]phenoxy}butanoic acid, tert-
butyl ester (5h) was prepared from 4-[3-(tert-butyloxycarbonyl)propoxy]-4′-
methoxybenzophenone 4e (1.85 g; 5.0 mmol) in dry THF (50 mL) and 1.0 M 2-
thienylmagnesium bromide (7.5 mL, 7.5 mmol). The crude compound was chromatographed on
silica gel in toluene with 1.0% of Et3N to give the desired tritanol as a violet oil. Yield 1.33 g
(58%). ESI-TOF HRMS: m/z = 565.2622 [M–OH]+, calc. for [C33H41O6S]+ 565.2618. NMR
(DMSO-d6): 7.40 (m, 1H, H-5 (thiophene)); 7.15 (m, 4H, ArH (phenyl)); 6.93 (m, 1H, H-4
(thiophene)); 6.84 (m, 4H, ArH (phenyl)); 6.62 (m, 1H, H-3 (thiophene)); 6.52 (s, 1H, OH); 3.94
(t, 2H, J = 6.4 Hz, OCH2); 3.73 (s, 3H, OCH3); 2.35 (t, 2H, J = 7.3 Hz, COCH2); 1.91 (m, 2H,
CH2CH2CH2), 1.39 (s, 9H, CCH3).
4-{4-[Hydroxy-(4-dimethylaminophenyl)-(4-methoxyphenyl)-methyl]phenoxy}butanoic
acid, tert-butyl ester (5i) was prepared from 4e (1.48 g; 4.0 mmol) in dry THF (30 mL) and 0.5
M 4-dimethylaminophenylmagnesium bromide (10.0 mL, 5.0 mmol). The compound was
chromatographed on silica gel in toluene with 1.0% of Et3N. Colourless oil, yield 1.514 g (77%).
ESI-TOF HRMS: m/z = 565.2622 [M–OH]+, calc. for [C30H36NO4]+ 565.2618. NMR (DMSO-
d6): 7.07 (m, 4H, ArH); 6.95 (d, 2H, J = 8.8 Hz, ArH); 6.81 (m, 4H, ArH); 6.62 (d, 2H, J = 8.8
Hz, ArH); 5.91 (s, 1H, OH); 3.94 (t, 2H, J = 6.3 Hz, OCH2); 3.72 (s, 3H, OCH3); 2.85 (s, 6H,
NCH3); 2.35 (t, 2H, J = 7.3 Hz, COCH2); 1.91 (m, 2H, CH2CH2CH2), 1.40 (s, 9H, CCH3).

4-[3-(tert-Butyloxycarbonyl)propoxy]-4′,4′′-dimethoxytritanol (5j) was prepared from
4e (1.85 g; 5.0 mmol) in dry THF (30 mL) and 1 M 4-methoxyphenylmagnesium bromide (7.0
mL, 7.0 mmol); the purification was achieved using chromatography on silica gel in 3→7%
EtOAc in toluene. The desired tritanol was obtained as a yellow oil, yield 1.79 g (75%). ESI-
TOF HRMS: m/z = 461.2325 [M–OH]+, calc. for [C29H33O5]+ 461.2323.
OMe
O
MeO
MgBr
/ THF
HO
O
O
MeO
O
MeO
O
O
O
5k
4f
6-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenoxy}hexanoic acid, tert-butyl ester (5k)
was prepared from 4-[5-(tert-butyloxycarbonyl)pentyloxy]-4′-methoxybenzophenone 4f (400
mg; 1.0 mmol) in dry THF (10 mL) and 1 M 4-methoxyphenylmagnesium bromide (1.2 mL, 1.2
mmol). The crude compound was chromatographed on silica gel in 0→15% EtOAc in toluene
with 0.5% of Et3N to give the desired tritanol as a colourless oil, yield 334 mg (66%). ESI-TOF
HRMS: m/z = 489.2630 [M–OH]+, calc. for [C31H37O5]+ 489.2636. NMR (DMSO-d6): 7.06 (m,
6H, ArH); 6.82 (m, 6H, ArH); 6.07 (s, 1H, OH); 3.92 (t, 2H, J = 6.2 Hz, OCH2); 3.72 (s, 6H,
OCH3); 2.20 (t, 2H, J = 7.3 Hz, COCH2); 1.69 (m, 2H), 1.54 (m, 2H), 1.39 (m, 2H),
(OCH2CH2CH2CH2); 1.37 (s, 9H, CCH3).
General procedure for preparation of trityl acids 6. To a stirred solution of tert-butyl ester 5
(3 mmol) in dry DCM (5 mL) trifluoroacetic acid (5 mL) was added in one portion and the
mixture was stirred at ambient temperature for 3 h, then evaporated, and co-evaporated with
DCM (4×50 mL) to give free acid. These were used for the preparation of activated esters
without additional purification. In some cases analytical samples of acids 6 were purified by
column chromatography on silica gel (typically 20 to 40% acetone in toluene).
General procedure for preparation of N-oxysuccinimide activated esters 7. The acid 6
obtained from tert-butyl ester 5 (3 mmol) were dissolved in DCM (50 mL), triethylamine (0.92
mL, 6.6 mmol) and N,N-disuccinimidyl carbonate (1.27 g, 4.95 mmol) were added and the
mixture was stirred overnight, then evaporated, dissolved in EtOAc (100 mL), washed with 5%
NaHCO3 (100 mL) and water (100 mL), dried over Na2SO4, and evaporated to give pure
activated ester 7. In some cases the latter was purified by column chromatography on silica gel
(EtOAc in toluene).
S
S
S
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
HO
O
O
O
OH
O
O
N
O
O
O
O
7a
O
5a
6a
4-{4-[Hydroxy-(2-thienyl)-phenylmethyl]phenoxy}butanoic acid, N-succinimidyl ester (7a)
was prepared from tert-butyl ester of 4-{4-[hydroxy-(2-thienyl)-phenylmethyl]phenoxy}butanoic
acid 5a (1.40 g; 3.3 mmol). The final compound purified by column chromatography (0→20%
EtOAc in toluene). Yield 1.00 g (65%), pink amorphous solid. ESI-TOF HRMS: m/z = 448.1217
[M–OH]+, calc. for [C25H22NO5S]+ 448.1213. NMR (DMSO-d6): 7.42 (m, 1H, H-5 (thiophene));
7.33–7.22 (m, 5H, ArH (phenyl)); 7.16 (d, 2H, J = 8.9 Hz, ArH (phenyl)); 6.94 (dd, 1H, J4,5
=
4.8 Hz, J3,4 = 3.6 Hz, H-4 (thiophene)); 6.87 (d, 2H, J = 8.9 Hz, ArH (phenyl)); 6.65 (m, 2H, H-3
(thiophene), OH); 4.03 (t, 2H, J = 6.3 Hz, OCH2); 2.84 (t, 2H, J = 7.4 Hz, COCH2); 2.81 (s, 4H,
COCH2CH2CO); 2.06 (m, 2H, CH2CH2CH2).

NMe2
NMe2
NMe2
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
HO
O
O
O
OH
O
O
N
O
O
O
O
7b
O
5b
6b
4-{4-[Hydroxy-(4-dimethylaminophenyl)-phenyl-methyl]phenoxy}butanoic
oxysuccinimide ester (7b) was prepared from tert-butyl
acid,
4-{4-[hydroxy-(4-
N-
dimethylaminophenyl)-phenyl-methyl]phenoxy}butanoate 5b (923 mg; 2.0 mmol). Column
chromatography: 5→10→15% EtOAc in toluene. Yield 458 mg (43%), pink amorphous solid.
ESI-TOF HRMS: m/z = 485.2075 [M–OH]+, calc. for [C29H29N2O5]+ 485.2071. NMR (DMSO-
d6): 7.26 (m, 2H, ArH); 7.19 (m, 3H, ArH); 7.07 (d, 2H, J = 8.7 Hz, ArH); 6.96 (d, 2H, J = 8.7
Hz, ArH); 6.84 (d, 2H, J = 8.7 Hz, ArH); 6.62 (d, 2H, J = 8.7 Hz, ArH); 6.03 (s, 1H, OH); 4.02
(t, 2H, J = 6.3 Hz, OCH2); 2.88–2.79 (m, 12H, NCH3, CH2CH2CH2CO, COCH2CH2CO); 2.06
(m, 2H, CH2CH2CH2).
OMe
OMe
OMe
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
HO
O
O
O
OH
O
O
N
O
O
O
O
7c
O
5c
6c
4-{4-[Hydroxy-(4-methoxyphenyl)-phenyl-methyl]phenoxy}butanoic
acid,
N-
oxysuccinimide ester (7c) was prepared from 4-[3-(tert-butyloxycarbonyl)propoxy]-4′-
methoxytritanol 5c (1.12 g; 2.5 mmol). Column chromatography: 5→20% EtOAc in toluene.
Yield 0.900 g (74%), white amorphous solid. ESI-TOF HRMS: m/z = 472.1751 [M–OH]+, calc.
for [C28H26NO6]+ 472.1755. NMR (DMSO-d6): 7.28 (m, 2H, ArH); 7.20 (m, 3H, ArH); 7.08 (m,
4H, ArH); 6.85 (m, 4H, ArH); 6.20 (s, 1H, OH); 4.03 (t, 2H, J = 6.2 Hz, OCH2); 3.73 (s, 3H,
OCH3); 2.84 (m, 6H, OCOCH2, COCH2CH2CO); 2.06 (m, 2H, CH2CH2CH2).
OMe
OMe
OMe
HO
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
O
O
O
OH
O
O
N
O
O
O
O
7d
O
5d
6d
6-{4-[Hydroxy-(4-methoxyphenyl)-phenyl-methyl]phenoxy}hexanoic
acid,
N-
oxysuccinimide ester (7d) was prepared from tert-butyl 6-{4-[hydroxy-(4-methoxyphenyl)-
phenyl-methyl]phenoxy}hexanoate 5d (953 mg; 2.0 mmol). Yield 743 mg (72%), white
amorphous solid. ESI-TOF HRMS: m/z = 500.2075 [M–OH]+, calc. for [C30H30NO6]+ 500.2068.
NMR (DMSO-d6): 7.26 (m, 2H, ArH); 7.20 (m, 3H, ArH); 7.07 (m, 4H, ArH); 6.83 (m, 4H,
ArH); 6.17 (s, 1H, OH); 3.93 (t, 2H, J = 6.2 Hz, OCH2); 3.73 (s, 3H, OCH3); 2.81 (s, 4H,
COCH2CH2CO); 2.69 (t, 2H, J = 7.2 Hz, COCH2); 1.78–1.64 (m, 4H, OCH2CH2CH2CH2), 1.51
(m, 2H, OCH2CH2CH2).

S
S
HO
HO
CF3CO2H / DCM
HO
OH
O
O
O
O
O
O
O
O
O
O
6e
5e
S
DSC / Et3N / DCM
O
HO
O
O
O
N
O
O
N
O
O
O
O
7e
2-Thienyl-4′,4′′-bis[3-(N-succinimidylcarbonyl)propoxy]triphenylmethanol
(7e)
was
prepared from 2-thienyl-4′,4′′-bis[3-(tert-butyloxycarbonyl)propoxy]triphenylmethanol 5e (2.50
g; 4.29 mmol). The compound was purified by column chromatography (10→50% EtOAc in
toluene). Yield 2.05 g (72%), pink amorphous solid. ESI-TOF HRMS: m/z = 647.1697 [M–
OH]+, calc. for [C33H31N2O10S]+ 647.1694. NMR (DMSO-d6): 7.41 (m, 1H, H-5 (thiophene));
7.16 (d, 4H, J = 8.8 Hz, ArH); 6.93 (dd, 1H, J4,5 = 4.8 Hz, J3,4 = 3.7 Hz, H-4 (thiophene)); 6.87
(d, 4H, J = 8.8 Hz, ArH); 6.63 (m, 1H, H-3 (thiophene)); 6.54 (s, 1H, OH); 4.03 (t, 4H, J = 6.2
Hz, OCH2); 2.87–2.78 (m, 12H, COCH2, COCH2CH2CO); 2.07 (m, 4H, CH2CH2CH2).
NMe2
NMe2
HO
HO
CF3CO2H / DCM
HO
OH
O
O
O
O
O
O
O
O
O
O
6f
5f
4-(N,N-Dimethylaminophenyl)-4′,4′′-bis[3-carboxypropoxy]triphenylmethanol (6f). To a
stirred solution of 4-(N,N-dimethylaminophenyl)-4′,4′′-bis[3-(tert-butyloxycarbonyl)propoxy]-
triphenylmethanol (1.55 g, 2.5 mmol) in dry DCM (5 mL) trifluoroacetic acid (5 mL) was added
in one portion and the mixture was stirred at ambient temperature overnight (monitoring by TLC
in EtOAc-toluene 1:4). The solution was evaporated to dryness, and co-evaporated with DCM
(4×30 mL) to give acid 6f as dark violet oil. Yield 1.23 g (97 %). ESI-TOF HRMS: m/z =
490.2220 [M–OH]+, calc. for [C29H32NO6]+ 490.2224. NMR (DMSO-d6): 7.49 (d, 2H, J = 9.6
Hz, ArH); 7.33 (d, 4H, J = 8.9 Hz, ArH); 7.27 (d, 2H, J = 9.6 Hz, ArH); 7.21 (d, 4H, J = 8.9 Hz,
ArH); 4.18 (t, 4H, J = 6.4 Hz, OCH2); 3.46 (s, 6H, NCH3); 2.43 (t, 4H, J = 7.2 Hz, COCH2); 2.01
(m, 4H, CH2CH2CH2).
OMe
OMe
HO
HO
CF3CO2H / DCM
HO
OH
O
O
O
O
O
O
O
O
O
O
6g
OMe
5g
DSC / Et3N / DCM
O
HO
O
O
O
N
O
O
N
O
O
O
O
7f
4-Methoxy-4′,4′′-bis{[3-(N-succinimidyl)oxycarbonyl]propoxy}triphenylmethanol (7f) was
prepared from 4,4′-bis[3-(tert-butyloxycarbonyl)propoxy]-4′′-(4-methoxybenzoyl)tritanol 5g
(1.21 g; 2.0 mmol) and purified by column chromatography (20→30% EtOAc in toluene). Yield
826 mg (78%), white amorphous solid. Rf 0.18 (toluene–EtOAc, 1:1). ESI-TOF HRMS: m/z =
671.2230 [M–OH]+, calc. for [C36H35N2O11]+ 671.2235. NMR (DMSO-d6): 7.10–7.04 (m, 6H,
ArH (phenyl)); 6.88–6.81 (m, 6H, ArH (phenyl)); 6.09 (s, 1H, OH); 4.03 (t, 4H, J = 5.3 Hz,

OCH2); 3.73 (s, 3H, OCH3); 2.87–2.77 (m, 12H, COCH2CH2CO, COCH2); 2.11–2.03 (m, 4H,
CH2CH2CH2).
S
S
S
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
HO
O
O
O
OH
MeO
O
N
MeO
O
MeO
O
O
O
O
7g
O
5h
6h
4-{4-[Hydroxy-(2-thienyl)-(4-methoxyphenyl)-methyl]phenoxy}butanoic
acid,
N-
succinimidyl ester (7g) was prepared from tert-butyl ester of 4-{4-[hydroxy-(2-thienyl)-(4-
methoxyphenyl)-phenoxy}butanoic acid 5h (1.25 g; 2.75 mmol) and purified by column
chromatography (0→20% EtOAc in toluene). Yield 1.06 g (78%), pink amorphous solid. ESI-
TOF HRMS: m/z = 478.1315 [M–OH]+, calc. for [C26H24NO6S]+ 478.1319. NMR (DMSO-d6):
7.41 (m, 1H, H-5 (thiophene)); 7.19–7.13 (m, 4H, ArH (phenyl)); 6.93 (dd, 1H, J4,5 = 4.8 Hz, J3,4
= 3.7 Hz, H-4 (thiophene)); 6.86 (m, 4H, ArH (phenyl)); 6.62 (m, 1H, H-3 (thiophene)); 6.54 (s,
1H, OH); 4.03 (t, 2H, J = 6.2 Hz, OCH2); 3.73 (s, 3H, OCH3); 2.90–2.79 (m, 6H, COCH2,
COCH2CH2CO); 2.06 (m, 2H, CH2CH2CH2).
NMe2
NMe2
NMe2
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
HO
O
O
O
OH
MeO
O
N
MeO
O
MeO
O
O
O
O
7h
O
5i
6i
4-{4-[Hydroxy-(4-dimethylaminophenyl)-(4-methoxyphenyl)-methyl]phenoxy}butanoic
acid, N-oxysuccinimide ester (7h) was prepared from tert-butyl 4-{4-[hydroxy-(4-
dimethylaminophenyl)-(4-methoxyphenyl)-methyl]phenoxy}butanoate 5i (983 mg; 2.0 mmol)
and purified by column chromatography (10→15% EtOAc in toluene). Yield 660 mg (62%),
violet amorphous solid. ESI-TOF HRMS: m/z = 515.2181 [M–OH]+, calc. for [C30H31N2O6]+
515.2177. NMR (DMSO-d6): 7.07 (m, 4H, ArH); 6.95 (d, 2H, J = 8.7 Hz, ArH); 6.82 (m, 4H,
ArH); 6.62 (d, 2H, J = 8.7 Hz, ArH); 5.92 (s, 1H, OH); 4.02 (t, 2H, J = 6.3 Hz, OCH2); 3.72 (s,
3H, OCH3); 2.88–2.79 (m, 12H, NCH3, CH2CH2CH2CO, COCH2CH2CO); 2.06 (m, 2H,
CH2CH2CH2).
OMe
OMe
OMe
HO
CF3CO2H / DCM
DSC / Et3N / DCM
HO
HO
O
O
O
OH
MeO
O
N
MeO
O
MeO
O
O
O
O
7i
O
5j
6j
6-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenoxy}hexanoic acid, N-oxysuccinimide
ester (7i) was prepared from tert-butyl 6-{4-[hydroxy-bis(4-
methoxyphenyl)methyl]phenoxy}hexanoate 5j (253 mg; 0.5 mmol) and purified by column
chromatography (10→25% EtOAc in toluene). Yield 240 mg (88%), white amorphous solid.
ESI-TOF HRMS: m/z = 530.2175 [M–OH]+, calc. for [C31H32NO7]+ 530.2173. NMR (DMSO-
d6): 7.06 (m, 6H, ArH); 6.83 (m, 6H, ArH); 6.07 (s, 1H, OH); 3.93 (t, 2H, J = 6.2 Hz, OCH2);
3.72 (s, 3H, OCH3); 2.80 (s, 4H, COCH2CH2CO); 2.69 (t, 2H, J = 7.3 Hz, CH2CO2); 1.70 (m,
4H, OCH2CH2CH2CH2); 1.50 (m, 2H, OCH2CH2CH2).
General procedure for preparation of N-oxysulfosuccinimide activated esters.
A trityl acid (1.0 mmol), prepared as above, was dissolved in dry DMF (2.5 mL), then N-
oxysulfosuccinimide sodium salt (250 mg, 1.17 mmol) and DCC (375 mg, 1.8 mmol) were
added and the mixture was left under stirring overnight, then cooled to +4ºC and stirred for 2 h.

The precipitate formed was filtered off, and the solution was diluted with EtOAc (10 mL),
cooled to +4ºC overnight, filtered, and diluted with dry Et2O (200 mL). The mixture was kept at
ambient temperature for 2-3 h and the desired compound was collected by filtration, washed with
ether and dried in vacuo.
4-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenoxy}butyric acid, N-oxysulfosuccinimide
ester, sodium salt (8) was prepared using above procedure, 38% yield from the orthoester. ESI-
TOF HRMS: m/z = 604.1262 [M–OH]+, calc. for [C29H27NNaO10S]+ 604.1248. NMR (DMSO-
d6): 7.10-7.04 (m, 6H, ArH); 6.88-6.80 (m, 6H, ArH); 6.09 (s, 1H, OH); 4.02 (t, 2H, J = 6.3 Hz,
OCH2); 3.73 (s, 6H, OCH3, CH); 2.91–2.79 (m, 4H, COCH2, COCH2CHCO); 2.10-2.02 (m, 2H,
CH2CH2CH2).
OMe
OMe
(PfpO)2CO / Et3N / DCM
F
HO
HO
F
F
O
O
F
F
F
HO
OH
O
O
O
O
O
O
O
O
F
F
6g
9
F
F
4,4′-Bis[3-(pentafluorophenyloxyacarbonyl)propoxy]-4′′-methoxy-tritanol (9). To a stirred
solution of 4,4′-bis(3-carboxypropoxy)-4′′-methoxy-tritanol (742 mg; 1.5 mmol) in dry DCM (20
mL) triethylamine (0.28 mL, 2.0 mmol) pentafluorophenyl carbonate (1.97 g, 5.0 mmol) were
added and the mixture was stirred overnight, then evaporated, coevaporated with DCM and
chromatographed on silica gel (5→10% EtOAc in toluene). Yield 980 mg (79%), dark red oil Rf
0.25 (toluene–EtOAc, 3:1). ESI-TOF HRMS: m/z = 809.1595 [M–OH]+, calc. for [C40H27F10O7]+
809.1592.
General procedure for preparation of amides 10.
Succinimide activated ester (1 mmol) in DCM (20 mL) was treated with amine (2.5 mmol) for 3
h. The solution was then washed with water, 5% citric acid, dried, and evaporated. The residue
was purified by column chromatography in appropriate solvent system. Yields are usually >
90%.
Examples of preparation of amides 10.
NMe2
NMe2
PyBOP / DIEA / DMF
HO
HO
H
N
OH
MeO
O
MeO
O
O
O
10a
6i
4-{4-[Hydroxy-(4-dimethylaminophenyl)-(4-methoxyphenyl)-methyl]phenoxy}butanoic
acid, 4-phenylbutylamide (10f). To stirred solution of 4-{4-[hydroxy-(4-
a
dimethylaminophenyl)-(4-methoxyphenyl)-methyl]phenoxy}butanoic acid 6i (245 mg, 0.56
mmol) in dry DMF (10 mL) N,N-diisopropylethylamine (145 μL, 0.84 mmol) and PyBOP (350
mg, 0.67 mmol) were subsequently added. The mixture was stirred 10 min at ambient
temperature, and 4-phenylbutylamine (167 μL, 1.12 mmol) was added. The mixture was stirred
then 1 h, diluted with EtOAc (200 mL), washed with water (4×100 mL), dried over Na2SO4, and
chromatographed on silica gel in toluene with 10→15% of EtOAc and 0.5% Et3N. The product
was obtained as pale pink oil (275 mg), yield 86%. ESI-TOF HRMS: m/z = 549.3107 [M–OH]+,
calc. for [C36H41N2O3]+ 549.3112. NMR (DMSO-d6): 7.80 (m, 1H, NH); 7.30–7.10 (m, 5H,
ArH); 7.06 (m, 4H, ArH); 6.95 (d, 2H, J = 8.8 Hz, ArH); 6.80 (m, 4H, ArH); 6.61 (d, 2H, J = 8.8
Hz, ArH); 5.91 (s, 1H, OH); 3.91 (t, 2H, J = 6.3 Hz, OCH2); 3.72 (s, 3H, OCH3); 3.06 (m, 2H,

NCH2); 2.85 (s, 6H, NCH3); 2.55 (m, 2H, PhCH2); 2.20 (t, 2H, J = 7.3 Hz, COCH2); 1.91 (m,
2H, COCH2CH2), 1.54 (m, 2H, PhCH2CH2), 1.39 (m, 2H, NCH2CH2).
OMe
OMe
Py / H2O
HO
HO
O
H
O
N
MeO
O
N
MeO
O
NMe3
Cl
O
O
8
10g
O
SO3Na
4-{3-[2-(Trimethylamino)ethylaminocarbonyl]propoxy}phenyl-4′,4′′-dimethoxytritanol
(10g). To a stirring solution of 2-aminoethyl-trimethylammonium chloride (69 mg, 0.5 mmol) in
the mixture of pyridine (1 mL), acetonitrile (1 mL), and water (1 mL) 4-[3-(sulfosuccinimido-
oxycarbonyl)propoxy]phenyl-4′,4′′-dimethoxytritanol, sodium salt, 8 (155 mg, 0.25 mmol) was
added in one portion and the mixture was stirred for 6h, then diluted with CHCl3 (50 mL),
washed with water (100 mL), brine (100 mL), dried over Na2SO4, and evaporated to dryness.
The residue was dissolved in acetone (2 mL) and precipitated in Et2O to give pure 10b as white
solid (95 mg, 70%). ESI-TOF HRMS: m/z = 490.2830 [M–OH]+, calc. for [C30H38N2O4]+
1
490.2826. H NMR (DMSO-d6): 8.48 (m, 1H, NH); 7.21 (m, 2H, ArH); 7.06 (m, 4H, ArH);
6.90–6.80 (m, 6H, ArH); 6.09 (s, 1H, OH); 3.94 (m, 2H, OCH2); 3.73 (s, 3H), 3.72 (s, 3H)
(OCH3); 3.48 (m, 2H, NHCH2); 3.39 (m, 2H, NHCH2CH2); 3.11 (s, 9H, CCH3); 2.29 (t, 2H, J =
13
7.2 Hz, COCH2); 1.94 (m, 2H, COCH2CH2). C NMR (DMSO-d6): 172.26 (CO), 157.80 (2C,
C4′,4′′), 157.07 (C4), 140.57 (2C, C1′,1′′), 136.21 (C1), 129.43 (2C, C2,6), 128.89 (4C,
C2′,6′,2′′,6′′), 113.16 (2C, C3,5), 112.76 (4C, C3′,5′,3′′,5′′), 79.64 (Ar3COH), 66.81, 55.06 (2C,
4′-OCH3, 4′′-OCH3), 52.60, 33.10, 31.67, 29.64, 24.75.
MeO
OMe
OMe
OH
HO
O
O
O
MeO
O
N
O
O
SO3Na
8
OMe
O
NH
HN
O
N
HO
O
O
H
N
H
NH2
N
O
OMe
MeO
O
N
N
N
H
H
O
O
O
HN
O
N
OH
O
NH
O
H
H2N
N
N
H
N
NH2
HN
O
OMe
O
O
NH
10h
NH2
OH
MeO
OMe
N,N,N′,N′-Tetrakis{2-[2-(4-{4-[bis(4-methoxyphenyl)hydroxymethyl]phenoxy}butyryl-
amino)ethylaminocarbonyl]ethyl}ethylenediamine (10h). To a stirring solution of N,N,N’,N’-
tetrakis[2-(2-aminoethylaminocarbonyl)ethyl]ethylenediamine (103 mg, 0.2 mmol) in the
mixture of MeOH (1 mL), acetonitrile (1 mL), and water (1 mL) 4-[3-(sulfosuccinimido-
oxycarbonyl)propoxy]phenyl-4’,4’’-dimethoxytritanol, sodium salt, 8 (622 mg, 1.0 mmol) was
added in one portion and the mixture was stirred for 6h, then diluted with CHCl3 (50 mL),
washed with water (2×100 mL), dried over Na2SO4, and evaporated to dryness. The residue was
chromatographed on silica gel in 0→10% MeOH in Me2CO to give 10h as white amorphous
solid. Yield (326 mg, 76%). Rf 0.60 (acetone–MeOH, 1:1 + 0.5% Et3N). ESI-TOF HRMS: m/z =
2116.0329 [M–OH]+, calc. for [C122H143N10O23]+ 2116.0322. 1H NMR (DMSO-d6): 7.92 (m, 4H,

NH); 7.87 (m, 4H, NH); 7.20 (m, 8H, ArH); 7.05 (m, 16H, ArH); 6.88–6.78 (m, 24H, ArH); 6.07
(br.s, 4H, OH); 3.91 (m, 8H, OCH2); 3.71 (s, 24H, OCH3); 3.07 (br.s, 16H, COCH2CH2N); 2.87
(s, 4H, NCH2CH2N); 2.61 (m, 8H, COCH2); 2.19 (m, 16H, NHCH2CH2NH); 1.90 (m, 8H,
13
OCH2CH2). C NMR (DMSO-d6): 171.79 (4C, CO), 171.56 (4C, CO), 157.92, 157.79, 157.28,
157.12, 140.58, 140.52, 136.27, 136.12, 129.46, 129.41, 128.89 (16C), 113.61, 113.26, 113.13,
112.74 (16C), 85.56, 79.64 (4C), 68.54, 66.90, 55.88, 55.03 (8C), 51.25, 50.95, 49.73, 38.45,
38.35, 33.51, 31.13, 31.82, 29.65, 24.91.
CHO
O
CO2H
.
Et3N 2.5 HCO2H
O
+
Br
O
O
Br
3-(4-Bromophenyl)propionic acid. 4-Bromobenzaldehyde (92.5 g, 0.50 mol) and Meldrum’s
acid (72.0 g, 0.50 mol) were dissolved in triethylamine–formic acid reagent[4] (1.5 L) and the
mixture was refluxed for 20 h, then diluted with water (4 L) and acidified with 6N HCl (1 L)
until pH reached 2. The precipitated solid was filtered off, washed with diluted HCl, and
dissolved in 5% NaHCO3. The aqueous salt solution was washed with ether (4x400 mL), filtered
and acidified with diluted HCl. The resulting 3-(4-bromophenyl)propionic acid was filtered off
and dried in vacuo over KOH and P4O10, yield 69.4 g (60 %). The compound was pure according
to NMR. Rf 0.33 (CHCl3–EtOAc, 9:1). An analytical sample was crystallyzed from toluene and
showed mp 134ºC. NMR (DMSO-d6): 9.52 (br. s, 1H, OH); 8.00 (d, 2H, J = 8.1 Hz, ArH); 7.73
(d, 2H, J = 8.1 Hz, ArH), 3.41 (t, 2H, J = 7.5 Hz, ArCH2), 3.14 (t, 2H, J = 7.5 Hz, CH2CO). The
compound is also available from Aldrich.
O
1. SOCl2
O
CO2H
O
2. HO
O
Br
Br
pyridine / DCM
(3-Methyl-3-oxetanyl)methyl 3-(4-bromophenyl)propionate. 3-(4-Bromophenyl)propionic
acid chloride was prepared in usual manner from 3-(4-bromophenyl)propionic acid (5.50 g, 24
mmol) and oxalyl chloride (4.2 ml, 50 mmol) in benzene (30 mL) with following evaporation. 3-
Methyl-3-oxetanemethanol (2.30 ml, 23 mmol) and pyridine (3.8 mL, 48 mmol) were dissolved
in DCM (50 mL) and crude 3-(4-bromophenyl)propionyl chloride in DCM (10 mL) was added
dropwise within 30 min with stirring and cooling on a water bath. The mixture was stirred for 16
h, then diluted with CHCl3 (200 mL), washed with water (2x200 mL), 5% NaHCO3 (2x200 mL),
5% citric acid (3x100 mL) and 10% NaHCO3 (100 mL), dried over Na2SO4, evaporated and
chromatographed on silica gel in CHCl3. Yield 5.90 g (82%). Colorless oil which solidifies upon
storage, mp around 30ºC. Rf 0.20 (toluene–EtOAc, 9:1). NMR (CDCl3): 7.39 (d, 2H, J = 8.2 Hz,
ArH); 7.07 (d, 2H, J = 8.2 Hz, ArH); 4.44 (d, 2H, J = 6.0 Hz), 4.34 (d, 2H, J = 6.0 Hz)
(CH2OCH2); 4.13 (s, 2H, CH2OCO); 2.91 (t, 2H, J = 7.6 Hz, ArCH2), 2.66 (t, 2H, J = 7.6 Hz,
CH2CO); 1.27 (s, 3H, CH3).
O
O
.
BF3 Et2O / DCM
O
O
O
O
Br
Br
11a
1-[2-(4-Bromophenyl)ethyl]-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane (11a). 3-Methyl-3-
oxetanyl)-methyl 3-(4-bromophenyl)propionate (31.32 g, 100 mmol) was dissolved in dry DCM
(100 mL), cooled on NaCl–ice bath to -15ºC, and boron trifluoride diethyl etherate (3.1 mL, 25
mmol) was added in one portion. The mixture was stirred for 1h, then allowed to warm to room
temperature, quenched with triethylamine (14 mL, 100 mmol) and diluted with diethyl ether (150
mL). The boron trifluoride–diethyl ether complex was filtered off, the solution was evaporated,
and the residue was purified by flash chromatography on silica gel in toluene. Finally, the
compound was crystallyzed from toluene–petroleum ether to give colorless needles (24.86 g,

79%), mp 184ºC (toluene–petroleum ether). Rf 0.35 (toluene–EtOAc, 9:1). ESI-TOF HRMS: m/z
= 313.0428 [M+H]+, calc. for [C14H18BrO3]+ 313.0434. NMR (DMSO-d6): 7.43 (d, 2H, J = 8.3
Hz, ArH); 7.14 (d, 2H, J = 8.3 Hz, ArH); 3.84 (s, 6H, CH2O); 2.62 (m, 2H, ArCH2); 1.82 (m, 2H,
ArCH2CH2); 0.76 (s, 3H, CH3).
O
Br
CN
O
O
1.
CN
1. HCl/MeOH
OH
K2CO3 / acetone
Br
OH
Br
O
Br
O
2.
11b
OH
OH
4-(4-Bromophenoxy)butyronitrile. To a solution of 4-bromophenol (17.3 g, 0.10 mol) in
dry acetone (300 mL) dry K2CO3 (70 g, 0.5 mol) and 4-bromobutyronitrile (16.3 g, 0.11 mol)
were added, and the mixture was refluxed for approximately 10h, until starting 4-bromophenol
consumes (monitoring by TLC in CHCl3). The mixture was cooled, filtered, and solid inorganic
salts were washed with acetone. The combined filtrate was evaporated, and the residue was
dissolved in CHCl3 (100 mL), filtered again, and evaporated. The residue was triturated in
petroleum ether, filtered, and dried in vacuo to give desired aryl alkyl ether (22.3 g, 93%) as
colorless crystals, mp 62ºC, Rf 0.57 (toluene–EtOAc, 4:1). NMR (DMSO-d6): 7.45 (d, 2H, J =
9.0 Hz, ArH); 6.92 (d, 2H, J = 9.0 Hz, ArH); 4.02 (t, 2H, J = 6.1 Hz, OCH2); 2.64 (t, 2H, J = 7.1
Hz, CH2CN); 2.01 (m, 2H, CH2CH2CH2); NMR (CDCl3): 7.37 (d, 2H, J = 8.9 Hz, ArH); 6.77 (d,
2H, J = 8.9 Hz, ArH); 4.03 (t, 2H, J = 5.7 Hz, OCH2); 2.57 (t, 2H, J = 7.1 Hz, CH2CN); 2.01 (m,
2H, CH2CH2CH2).
1-[3-(4-Bromophenoxy)propyl]-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane (11b). An ice
cooled solution of 4-(4-bromophenoxy)butyronitrile (15.4 g, 64 mmol) in dry Et2O (50 mL) and
dry MeOH (2.6 mL, 64 mmol) was saturated with dry HCl within 3 h and then kept overnight at
ambient temperature. The precipitate formed was filtered off, washed with Et2O, and suspended
in the mixture of Et2O (70 mL) and MeOH (20 mL), then refluxed for 48 h and cooled. The solid
was filtered off, the filtrate was evaporated, diluted with petroleum ether (100 mL) and filtered
again. The filtrate was evaporated, dissolved in dry MeOH (30 mL), then 1,1,1-
tris(hydrohymethyl)ethane (9.01 g, 75 mmol) and BF3 etherate (0.15 mL, 1.1 mmol) were added.
The mixture was stirred for 3 h, evaporated, and the residue was chromatographed on silica gel
column in 0→5% EtOAc in toluene containing 1% Et3N to yield the desired orthoester (6.13 g,
28%) as a colorless solid, mp 93ºC, Rf 0.55 (toluene–EtOAc, 4:1). ESI-TOF HRMS: m/z =
343.0548 [M+H]+, calc. for [C15H20BrO4]+ 343.0539. NMR (DMSO-d6): 7.41 (d, 2H, J = 8.9 Hz,
ArH); 6.87 (d, 2H, J = 8.9 Hz, ArH); 3.94 (t, 2H, J = 6.3 Hz, ArOCH2); 3.82 (s, 6H, OCH2);
1.80–1.67 (m, 4H, OCH2CH2CH2); 0.74 (s, 3H, CH3).
General procedure for preparation of tritanol orthoesters 12. To a stirred and coolled to -
70ºC mixture of THF (20 mL) and 0.9 M BuLi in hexane (7.0 mL, 6.3 mmol) the solution of
bromo orthoester 11a or 11b (5.0 mmol) in THF (50 mL) was added dropwise within 30 min.
The mixture was then stirred for 30 min, and the solution of corresponding benzophenone (5.0
mmol) in THF (50 mL) was added dropwise within 30 min. The mixture was allowed to warm to
room temperature and stirred overnight at ambient temperature. The solution was evaporated to
dryness, the residue was dissolved in EtOAc (200 mL) with few drops of triethylamine, washed
with 5% NaHCO3 (2×200 mL), water (2×200 mL), dried over Na2SO4, and evaporated. The
residue was dissolved in toluene containing 1% Et3N (10 mL) and chromatographed on a silica
gel column in appropriate solvent system. The desired product was triturated in petroleum ether
filtered off and dried in vacuo.

OMe
O
O
1. Mg / THF
O
O
O
O
O
HO
Br
2.
MeO
OMe
12a
11a
OMe
1-(2-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenyl}ethyl)-4-methyl-2,6,7-
trioxabicyclo-[2.2.2]octane (12a). Method A. Magnesium turnings (0.30 g, 12.5 mmol) was
placed in a three-neck flask (250 mL) and activated by heating with a iodine crystal. The flask
was then equipped with dropping funnel, reflux condenser, and argon inlet. THF (20 mL) was
added to magnesium and 5–7 mL of the solution of 1-[2-(4-bromophenyl)ethyl]-4-methyl-2,6,7-
trioxabicyclo[2.2.2]octane (3.13 g, 10 mmol) in THF (40 mL) was added. The mixture was
heated under Ar near to boiling until a reaction started, then the remaining aryl bromide was
added dropwise and the mixture was refluxed for 30 min. Using Ar pressure, the solution was
filtered through glass wool in a 250 mL flask containing a solution of 4,4’-
dimethoxybenzophenone (2.42 g, 10 mmol) in THF (40 mL). The mixture was refluxed for 2 h,
then cooled, quenched with 5% NaHCO3 (200 mL), and extracted with EtOAc (2x100 mL). The
organic layer was separated, dried over Na2SO4, and evaporated. The residue was
chromatographed on silica gel column (2→10% EtOAc in toluene containing 0.5% Et3N). The
resulting oil was triturated in petroleum ether to give the desired to give the desired tritanol (1.50
g, 31%) colorless crystals, mp 145ºC (dec.). Rf 0.44 (toluene–EtOAc, 1:1), Rf 0.14 (toluene–
EtOAc, 9:1). ESI-TOF HRMS: m/z = 459.2175 [M–OH]+, calc. for [C29H31O5]+ 459.2166. NMR
(DMSO-d6): 7.07 (m, 8H, ArH); 6.83 (d, 4H, J = 8.8 Hz, ArH); 6.11 (s, 1H, OH); 3.84 (s, 6H,
CH2O); 3.72 (s, 6H, OCH3); 2.62 (m, 2H, ArCH2); 1.81 (m, 2H, ArCH2CH2); 0.76 (s, 3H,
CCH3). Method B. Following the general procedure for compounds 12, tritanol 12a was
obtained in 85% yield.
O
O
O
O
1. BuLi / THF
O
O
O
Br
HO
2.
S
11a
S
12b
3-[4-(9-Hydroxythioxanthen-9-yl)phenyl] propionic acid, N-oxysuccinimide ester (12b) was
prepared from alkyl orthoester and thioxanthone. ESI-TOF HRMS: m/z = 429.1510 [M–OH]+,
calc. for [C27H25O3S]+ 429.1519. NMR (DMSO-d6): 8.02 (d, 2H, J = 7.8 Hz, ArH
(thioxanthene)); 7.46–7.38 (m, 4H, ArH (thioxanthene)); 7.35–7.28 (m, 2H, ArH
(thioxanthene)); 7.07 (d, 2H, J = 8.2 Hz, ArH (phenyl)); 6.78 (m, 2H, ArH (phenyl)); 5.75 (s,
1H, OH); 2.93–2.86 (m, 2H, ArCH2); 2.85–2.74 (m, 6H, ArCH2CH2, COCH2CH2CO).
SMe
O
O
1. BuLI / THF
O
O
O
O
O
HO
Br
2.
MeS
SMe
12c
11a
SMe

1-(2-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenyl}ethyl)-4-methyl-2,6,7-
trioxabicyclo[2.2.2]octane (12c) was prepared from 1-[2-(4-bromophenoxy)ethyl]-4-methyl-
2,6,7-trioxabicyclo[2.2.2]octane (1.566 g, 5.0 mmol) and 4,4’-dimethylthiobenzophenone (1.372
g,
5.0
mmol).
The
compound
was
purified
using
stepwise
gradient
2→2.5→3.5→4.0→4.5→5.0% Me2CO in toluene containing 0.5% Et3N. Yield 1.249 g (49.1%),
amorphous solid. Rf 0.53 (toluene–EtOAc, 4:1). ESI-TOF HRMS: m/z = 491.1720 [M–OH]+,
calc. for [C29H31O3S2]+ 491.1709. NMR (DMSO-d6): 7.20–7.05 (m, 12H, ArH); 6.30 (s, 1H,
OH); 3.84 (s, 6H, CH2O); 2.63 (m, 2H, ArCH2); 2.44 (s, 6H, SCH3); 1.81 (m, 2H, ArCH2CH2);
0.76 (s, 3H, CCH3).
O
O
O
O
1. BuLi / THF
O
O
O
Br
HO
2.
S
OMe
11a
S
OMe
12d
1-{2-[4-(9-Hydroxy-3-methoxythioxanthen-9-yl)phenyl]ethyl}-4-methyl-2,6,7-trioxabicyclo-
[2.2.2]octane (12d) was prepared from 11a (845 mg, 2.70 mmol) and of 3-
methoxythioxanthone[5] (653 g, 2.70 mmol). Purification in 10% acetone in toluene containing
0.5% Et3N. Yield 1.14 g (94%), white amorphous solid. ESI-TOF HRMS: m/z = 459.1637 [M–
OH]+, calc. for [C28H27O4S]+ 459.1625. NMR (DMSO-d6): 7.98 (d, 1H, J = 7.8 Hz, H–8
(thioxanthene)); 7.86 (d, 1H, J = 8.7 Hz, H–1 (thioxanthene)); 7.42–7.36 (m, 2H, H–5,7
4
(thioxanthene)); 7.29 (m, 1H, H–6 (thioxanthene)); 7.00–6.94 (m, 2H, J = 2.6 Hz, H–2,4
(thioxanthene)); 6.93 (d, 2H, J = 8.0 Hz, ArH (C6H4)); 6.77 (d, 2H, J = 8.0 Hz, ArH (C6H4));
6.63 (s, 1H, OH); 3.81 (s, 6H, OCH2); 3.78 (s, 3H, OCH3); 2.52 (m, 2H, ArCH2); 1.71 (m, 2H,
ArCH2CH2); 0.74 (s, 3H, CCH3).
O
O
O
O
1. BuLi / THF
O
O
O
Br
HO
2.
MeO
S
OMe
MeO
11a
S
OMe
12e
1-{2-[4-(9-Hydroxy-3,6-dimethoxythioxanthen-9-yl)phenyl]ethyl}-4-methyl-2,6,7-trioxa-
bicyclo[2.2.2]octane (12e) was pepared from 11a (313 mg, 1.00 mmol) and 3,6-
dimethoxythioxanthone (272 mg, 1.00 mmol). The compound was chromatographed on silica gel
in 10→15% acetone in toluene containing 0.5% Et3N. Yield 415 mg (82%), white foam (from
DCM). ESI-TOF HRMS: m/z = 489.1717 [M–OH]+, calc. for [C29H29O5S]+ 489.1730. NMR
(DMSO-d6): 7.83 (d, 2H, J = 8.5 Hz, H–1,8 (thioxanthene)); 6.95 (m, 6H, H–2,4,5,7
(thioxanthene), ArH (C6H4)); 6.79 (d, 2H, J = 7.8 Hz, ArH (C6H4)); 6.53 (s, 1H, OH); 3.81 (s,
6H, OCH2); 3.77 (s, 6H, OCH3); 2.52 (m, 2H, ArCH2); 1.71 (m, 2H, ArCH2CH2); 0.74 (s, 3H,
CCH3).

O
O
O
O
1. BuLi / THF
O
O
O
Br
HO
2.
MeO
O
OMe
MeO
11a
O
OMe
12f
1-{2-[4-(9-Hydroxy-3,6-dimethoxyxanthen-9-yl)phenyl]ethyl}-4-methyl-2,6,7-trioxabicyclo-
[2.2.2]octane (12f) was prepared from 11a (5.86 g, 0.0187 mol) and 3,6-dimethoxyxanthone (4
g, 0.0187 mol). The compound was chromatographed on a silica gel. The column was eluted
with 10% acetone in toluene containing 0.5% Et3N. Yield 2.4 g, 31.3%. ESI-TOF HRMS: m/z =
1
473.1975 [M–OH]+, calc. for [C29H29O6]+ 473.1959. H NMR (200MHz, CDCl3) δ 8.2 (d, J =
8.8 Hz, 1H), 7.4 (d, J = 8.4 Hz, 1H), 6.8 (m, 7H), 6.5 (m, 1H), 3.8 (m, 12H), 2.7 (m, 2H), 2 (m,
2H), 0.8 (s, 3H).
OMe
O
O
O
O
1. BuLI / THF
O
O
O
O
HO
O
Br
2.
11b
MeO
OMe
12g
OMe
1-(3-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenoxy}propyl)-4-methyl-2,6,7-trioxa-
bicyclo[2.2.2]octane (12g) was prepared from 1-[3-(4-bromophenoxy)propyl]-4-methyl-2,6,7-
trioxabicyclo[2.2.2]octane 11b (1.716 g, 5.0 mmol) and 4,4’-dimethoxybenzophenone (1.211 g,
5.0 mmol). The trityl orthoester was purified on silica gel using stepwise gradient 5→10→15%
EtOAc in toluene containing 1% Et3N. The desired product was triturated in petroleum ether
filtered off and dried in vacuo. Yield 720 mg (28%), colorless crystals, mp 132ºC (dec.). Rf 0.40
(toluene–EtOAc, 1:1). ESI-TOF HRMS: m/z = 489.2284 [M–OH]+, calc. for [C30H33O6]+
489.2272.
SMe
O
O
O
O
1. BuLI / THF
O
O
O
O
HO
O
Br
2.
11b
MeS
SMe
12h
SMe
1-(3-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenoxy}propyl)-4-methyl-2,6,7-trioxa-
bicyclo[2.2.2]octane (12h) was prepared from 11b (1.716 g, 5.0 mmol) and 4,4’-
bis(methylthio)benzophenone (1.372 g, 5.0 mmol). The desired tritanol ortho ester was isolated
by a column chromatography. The column was eluted with stepwise gradient 8→12→15%
EtOAc in toluene containing 1% Et3N. The isolated 12h (810 mg, 1.5 mmol, 30% yield) was
used in the next step without purification.

O
O
O
O
O
OH
O
OH
OH
O
n
Ar1
Ar2
O
O
n
Ar1
Ar2
n
Ar1
Ar2
OH
OH
14
13
OH
12
General procedure for preparation of tritanol acids 14. Orthoester 12 (5.0 mmol) was
dissolved in the THF–water mixture (9:1, 10 mL), and trifluoroacetic acid (0.77 mL, 10 mmol)
was added. After stirring for 10 min the mixture was evaporated and diluted with 10 % NaOH in
ethanol–water (8:2, 30mL). The reaction mixture was refluxed for 30 min, cooled, and
evaporated, the residue was diluted with water (50 mL), washed with Et2O (2×50 mL), filtered,
acidified with 5% oxalic acid, and extracted with ethyl acetate (3×50 mL). The solution was
dried with Na2SO4, evaporated, and the residue was purified by column chromatography in an
appropriate solvent system.
Intermediate diolesters isolated by chromatography:
3-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenyl}propionic acid, 2-hydroxymethyl-2-
methyl-3-hydroxypropyl ester (13a), colorless oil. ESI-TOF HRMS: m/z = 477.2261 [M–
OH]+, calc. for [C29H33O6]+ 477.2272. NMR (DMSO-d6): 7.15–7.04 (m, 8H, ArH); 6.83 (m, 4H,
ArH); 6.13 (s, 1H, COH); 4.44 (t, 2H, J = 5.4 Hz, CH2OH); 3.87 (s, 2H, CH2OCO); 3.72 (s, 6H,
OCH3); 3.24 (m, 4H, CH2OH); 2.83 (t, 2H, J = 7.6 Hz, ArCH2); 2.61 (t, 2H, J = 7.6 Hz,
COCH2); 0.74 (s, 3H, CCH3).
3-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenyl}propionic acid 2-hydroxymethyl-2-
methyl-3-hydroxypropyl ester (13c) was obtained as a colorless oil, yield 895 mg (85%). ESI-
TOF HRMS: m/z = 509.1829 [M–OH]+, calc. for [C29H33O4S2]+ 509.1815. NMR (DMSO-d6):
7.20–7.07 (m, 12H, ArH); 6.32 (s, 1H, trityl OH); 4.43 (m, 2H, CH2OH); 3.87 (s, 2H, CH2OCO);
3.24 (m, 4H, CH2OH); 2.84 (m, 2H, ArCH2); 2.62 (m, 2H, CH2CO); 2.44 (s, 6H, SCH3); 0.74 (s,
3H, CCH3).
O
O
O
N
O
n
Ar1
Ar2
O
O
O
OH
OH
15
n
Ar1
Ar2
O
O
OH
O
SO3Na
14
O
N
n
Ar1
Ar2
O
OH
16
Acids 14 were converted to the activated esters 15 and 16 using general procedures for
corresponding esters 7 and 8.
3-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenyl}propionic acid, N-oxysuccinimide ester
(15a) was prepared from 12a (2.38 g, 5.0 mmol) and purified by column chromatography (10 to
40% EtOAc in toluene). Yield 2.05 g (86%), white amorphous solid. Rf 0.31 (toluene–EtOAc,
1:1). ESI-TOF HRMS: m/z = 472.1770 [M–OH]+, calc. for [C28H26NO6]+ 472.1755. NMR
(DMSO-d6): 7.20 (d, 2H, J = 8.3 Hz, ArH); 7.12–7.05 (m, 6H, ArH); 6.83 (d, 4H, J = 9.0 Hz,
ArH); 6.15 (s, 1H, OH); 3.73 (s, 6H, OCH3); 3.02–2.90 (m, 4H, ArCH2CH2); 2.81 (s, 4H,
COCH2CH2CO).
3-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenyl}propionic acid, N-oxysuccinimide
ester (15c) 1-(2-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenyl}ethyl)-4-methyl-2,6,7-

trioxabicyclo-[2.2.2]octane (1.08 g, 2.0 mmol) was dissolved in the THF–water mixture (19:1,
10mL), and trifluoroacetic acid (0.08 mL, 1 mmol) was added. After stirring for 10 min the
mixture was evaporated, the residue was dissolved with EtOAc (200 mL), washed with 5%
NaHCO3 (100 mL) and water (2×100 mL), dried over Na2SO4, evaporated, and chromatographed
on silica gel column in 10 → 40% Me2CO in toluene to give 3-{4-[hydroxy-bis(4-
methylthiophenyl)methyl]phenyl}propionic
acid
2-hydroxymethyl-2-methyl-3-
hydroxypropyl ester (13c) as a colorless oil, yield 895 mg (85%). ESI-TOF HRMS: m/z =
509.1804 [M–OH]+, calc. for [C29H33O4S2]+ 509.1815. NMR (DMSO-d6): 7.20–7.07 (m, 12H,
ArH); 6.32 (s, 1H, trityl OH); 4.43 (m, 2H, CH2OH); 3.87 (s, 2H, CH2OCO); 3.24 (m, 4H,
CH2OH); 2.84 (m, 2H, ArCH2); 2.62 (m, 2H, CH2CO); 2.44 (s, 6H, SCH3); 0.74 (s, 3H, CCH3).
The ester was dissolved in 10% NaOH in ethanol–water (8:2, 10mL), stirred overnight, then
evaporated, coevaporated with water (2×50 mL), dissolved in water (100 mL), washed with ether
(2×100 mL), and then acidified with solid citric acid to pH 4. The reaction mixture was extracted
with EtOAc (2×100 mL), the combined organic layers were washed with water (50 mL), dried
over Na2SO4 and evaporated to dryness. The resulting 3-{4-[hydroxy-bis(4-
methylthiophenyl)methyl]phenyl}propionic acid (14c) was obtained as a colorless oil, 637 mg
(88%). ESI-TOF HRMS: m/z = 407.1140 [M–OH]+, calc. for [C24H23O2S2]+ 407.1134. NMR
(DMSO-d6): 12.09 (s, 1H, CO2H); 7.20–7.08 (m, 12H, ArH); 6.32 (s, 1H, trityl OH); 2.81 (m,
2H, ArCH2); 2.52 (m, 2H, CH2CO); 2.44 (s, 6H, SCH3). This was dissolved in anhydrous DCM
(20 mL) and triethylamine (0.35 mL, 2.5 mmol) and N,N’-disuccinimidyl carbonate (512 g, 2.0
mmol) were added and the mixture was stirred until the reaction is complete (monitoring by TLC
in toluene–EtOAc, 1:1), then evaporated, dissolved in EtOAc (200 mL), washed with 5%
NaHCO3 (100 mL) and water (100 mL), dried over Na2SO4, evaporated, and the residue was
purified by column chromatography (5 to 10% EtOAc in toluene). Yield 542 mg (69%), white
crystalline solid, mp 137ºC. Rf 0.36 (toluene–EtOAc, 4:1). ESI-TOF HRMS: m/z = 504.1282
[M–OH]+, calc. for [C28H26NO4S2]+ 504.1298. NMR (DMSO-d6): 7.24–7.10 (m, 12H, ArH);
6.34 (s, 1H, OH); 3.02–2.91 (m, 4H, ArCH2CH2); 2.81 (s, 4H, COCH2CH2CO); 2.45 (s, 6H,
SCH3).
3-[4-(9-Hydroxy-3-methoxythioxanthen-9-yl)phenyl]
propionic
acid,
N-
oxysuccinimide ester (15d). 1-{2-[4-(9-Hydroxy-3-methoxythioxanthen-9-yl)phenyl]ethyl}-4-
methyl-2,6,7-trioxabicyclo[2.2.2]octane (1.14 g, 2.54 mmol) was dissolved in the THF–water
mixture (4:1, 60 mL), and trifluoroacetic acid (290 µL, 3.82 mmol) was added. After stirring for
1 h the mixture was half evaporated, the residue was dissolved with EtOAc (100 mL), washed
with 5% NaHCO3 (100 mL) and water (2×100 mL), dried over Na2SO4 and evaporated. The
residue was dissolved in EtOH (120 mL), and NaOH (1.22 g, 30.5 mmol) was added. The
solution was stirred overnight at ambient temperature, filtered and evaporated. The residue was
dissolved in water (100 mL), washed with EtOAc (50 mL), acidified with solid citric acid to pH
3, and extracted with EtOAc (3×50 mL). Combined organic layers were dried over Na2SO4 and
evaporated to volume 30 mL. Triethylamine (1.76 mL, 13.7 mmol) and N,N′-disuccinimidyl
carbonate (1.95 g, 7.60 mmol) were added and the mixture was stirred until the reaction is
complete (monitoring by TLC), then dissolved in EtOAc (50 mL), washed with 5% NaHCO3
(2×50 mL) and water (50 mL), dried over Na2SO4, evaporated, and the residue was purified by
column chromatography (15% EtOAc in toluene). Yield 528 mg (45%), white amorphous solid.
ESI-TOF HRMS: m/z = 472.1208 [M–OH]+, calc. for [C27H22NO5S]+ 472.1213. NMR (DMSO-
d6): 7.99 (d, 1H, J = 7.8 Hz, ArH (thioxanthene)); 7.87 (d, 1H, J = 8.7 Hz, H-1 (thioxanthene));
7.39 (m, 2H, ArH (thioxanthene)); 7.29 (m, 1H, ArH (thioxanthene)); 7.07 (d, 2H, J = 8.2 Hz,
ArH (C6H4)); 7.00 (d, 1H, J = 2.5 Hz, H-4 (thioxanthene)); 6.96 (dd, 1H, J = 8.7 Hz, 4J = 2.5 Hz,
H-2 (thioxanthene)); 6.81 (d, 2H, J = 8.2 Hz, ArH (C6H4)); 6.67 (s, 1H, OH); 3.79 (s, 3H,
OCH3); 2.90 (m, 2H, ArCH2); 2.81 (m, 6H, COCH2).
3-[4-(9-Hydroxy-3,6-dimethoxythioxanthen-9-yl)phenyl] propionic acid, N-oxysuccinimide
ester (15e). 1-{2-[4-(9-Hydroxy-3,6-dimethoxythioxanthen-9-yl)phenyl]ethyl}-4-methyl-2,6,7-

trioxabicyclo[2.2.2]octane (253 mg, 0.50 mmol) was dissolved in the THF–water mixture (4:1,
20 mL), and trifluoroacetic acid (76 µL, 1.0 mmol) was added. After stirring for 1 h the mixture
was half evaporated, the residue was dissolved with EtOAc (50 mL), washed with 5% NaHCO3
(50 mL) and water (2×50 mL), dried over Na2SO4 and evaporated. The residue was dissolved in
EtOH (40 mL), and NaOH (0.61 g, 15 mmol) was added. The solution was stirred overnight at
ambient temperature, filtered and evaporated. The residue was dissolved in water (50 mL),
washed with EtOAc (50 mL), acidified with solid citric acid to pH 3, and extracted with EtOAc
(3×10 mL). Combined organic layers were dried over Na2SO4 and evaporated. Triethylamine
(0.59 mL, 4.5 mmol) and N,N′-disuccinimidyl carbonate (256 mg, 1.0 mmol) were added and the
mixture was stirred until the reaction is complete (monitoring by TLC), then dissolved in EtOAc
(50 mL), washed with 5% NaHCO3 (2×50 mL) and water (50 mL), dried over Na2SO4,
evaporated, and the residue was purified by column chromatography (15→20% EtOAc in
toluene). Yield 159 mg (61%), white amorphous solid. ESI-TOF HRMS: m/z = 502.1328 [M–
OH]+, calc. for [C28H24NO6S]+ 502.1319. NMR (DMSO-d6): 7.84 (d, 2H, J = 8.2 Hz, H–1,8
(thioxanthene)); 7.06 (d, 2H, J = 8.2 Hz, ArH (phenyl)); 6.98–6.92 (m, 4H, H–2,4,5,7
(thioxanthene)); 6.84 (d, 2H, J = 8.2 Hz, ArH (phenyl)); 6.57 (s, 1H, OH); 3.78 (s, 6H, CH3);
2.89 (m, 2H), 2.82 (m, 2H) (ArCH2CH2); 2.79 (br.s, 4H, COCH2CH2CO).
3-[4-(9-Hydroxy-3,6-dimethoxyxanthen-9-yl)phenyl] propionic acid, N-oxysuccinimide
ester (15f). 2 g of starting material (4.07 mmol) was dissolved in the THF-water mixture (4:1, 60
mL), and trifluoroacetic acid (374 µL, 4.89 mmol) was added. After stirring for 1 h the mixture
was half evaporated, the residue was dissolved with EtOAc (100 mL), washed with 5% NaHCO3
(100 mL) and water (2×100 mL), dried over Na2SO4 and evaporated. The residue was dissolved
in EtOH (120 mL), and NaOH (1.22 g, 30.5 mmol) was added. The solution was stirred
overnight at ambient temperature, filtered and evaporated. The residue was dissolved in water
(100 mL), washed with EtOAc (50 mL), acidified with solid citric acid to pH 3, and extracted
with EtOAc (3×50 mL). Combined organic layers were dried over Na2SO4 and evaporated to
volume 30 mL. Triethylamine (2.26 mL, 0.162 mol) and N,N′-disuccinimidyl carbonate (1.35 g,
5.27 mmol) were added and the mixture was stirred until the reaction is complete (monitoring by
TLC), then dissolved in EtOAc (50 mL), washed with 5% NaHCO3 (2×50 mL) and water (50
mL), dried over Na2SO4, evaporated, and the residue was purified by column chromatography
(15% EtOAc in toluene). Yield 1.45 g, 71%. ESI-TOF HRMS: m/z = 486.1559 [M–OH]+, calc.
1
for [C28H24NO7]+ 486.1547. H NMR (200MHz, CDCl3) δ 7 (m, 8H), 6.5 (m, 2H), 3.6 (s, 6H),
2.8 (s, 4H), 2.7 (m, 2H).
4-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenoxy}butanoic acid, N-oxysuccinimide
ester (15g). 1-(3-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenoxy}propyl)-4-methyl-2,6,7-
trioxabicyclo-[2.2.2]octane (1.01 g, 2.0 mmol) was dissolved in the THF–water mixture (4:1, 50
mL), and trifluoroacetic acid (0.23 mL, 3 mmol) was added. After stirring for 1 h the mixture
was half evaporated and diluted with EtOAc (200 mL), washed with water (100 mL), 5%
NaHCO3 (2×100 mL), evaporated. The resudue was dissolved in EtOH (100 mL), and NaOH
(1.0 g, 25 mmol) was added and dossolved in the mixture. The solution was stirred overnight at
ambient temperature, filtered and evaporated. The residue was dissolved in water (200 mL),
washed with Et2O (2×100 mL), acidified with solid citric acid to pH 3.5, and extracted with
EtOAc (3×100 mL). A combined organic lauer was dried over Na2SO4 and evaporated to volume
20 mL. Triethylamine (0.7 mL, 5.0 mmol) and N,N′-disuccinimidyl carbonate (0.64 g, 2.5 mmol)
were added and the mixture was stirred until the reaction is complete (monitoring by TLC in
toluene–acetone, 2:1), then evaporated, dissolved in EtOAc (200 mL), washed with 5% NaHCO3
(100 mL) and water (100 mL), dried with Na2SO4, evaporated, and the residue was purified by
column chromatography (10 to 30% EtOAc in toluene). Yield 0.800 g (77%), white amorphous
solid. Rf 0.30 (toluene–EtOAc, 1:1). ESI-TOF HRMS: m/z = 502.1848 [M–OH]+, calc. for
[C29H28NO7]+ 502.1860.

4-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenoxy}butyric acid, N-oxysuccinimide
ester (15h). To a stirred and coolled to -70ºC mixture of THF (40 mL) and 0.9M BuLi in hexane
(11.1 mL, 10 mmol) the solution of 1-[3-(4-Bromophenoxy)propyl]-4-methyl-2,6,7-
trioxabicyclo[2.2.2]octane (1.716 g, 5.0 mmol) in THF (50 mL) was added dropwise within 30
min. The mixture was left for 1h at -70ºC and the solution of 4,4′-bis(methylthio)benzophenone
(1.372 g, 5.0 mmol) in THF (50 mL) was added dropwise within 30 min. The mixture was
allowed to warm to room temperature and stirred overnight at ambient temperature. The solution
was evaporated to dryness, the residue was dissolved in EtOAc (200 mL), washed with 5%
NaHCO3 (2×200 mL), water (2×200 mL), dried with Na2SO4, and evaporated. The residue was
dissolved in toluene containing 1% Et3N (10 mL) and the desired tritanol ortho ester was isolated
by a column chromatography. The column was eluted with stepwise gradient 8→12→15%
EtOAc in toluene containing 1% Et3N. The isolated 1-(3-{4-[hydroxy-bis(4-
methylthiophenyl)methyl]phenyl}propoxy)-4-methyl-2,6,7-trioxabicyclo[2.2.2]octane (810 mg,
1.5 mmol, 30% yield) was dissolved in the THF–water mixture (19:1, 10mL), and trifluoroacetic
acid (0.08 mL, 1 mmol) was added. After stirring for 10 min the mixture was evaporated, the
residue was dissolved with EtOAc (200 mL), washed with 5% NaHCO3 (100 mL) and water
(2×100 mL), dried over Na2SO4, evaporated, diluted with 10 % NaOH in ethanol–water (8:2,
10mL), stirred overnight, then evaporated, coevaporated with water (2×50 mL), dissolved in
water (100 mL), washed with ether (2×100 mL), and then acidified with solid citric acid to pH 4.
The reaction mixture was extracted with EtOAc (2x100 mL), the combined organic layers were
washed with water (50 mL), dried over Na2SO4 and evaporated to dryness. The resulting acid
was dissolved in dry DCM (30 mL). Triethylamine (0.7 mL, 5 mmol) and N,N’-disuccinimidyl
carbonate (0.51 g, 2.0 mmol) were added and the mixture was stirred until the reaction is
complete (monitoring by TLC in toluene–EtOAc, 1:1), then evaporated, dissolved in EtOAc (200
mL), washed with 5% NaHCO3 (100 mL) and water (100 mL), dried with Na2SO4, evaporated,
and the residue was purified by column chromatography (10 to 40% EtOAc in toluene). Yield
348 mg (42% from ortho ester), white amorphous solid. ESI-TOF HRMS: m/z = 534.1415 [M–
OH]+, calc. for [C29H28NO5S2]+ 534.1403. NMR (DMSO-d6): 7.18 (d, 4H, J = 8.5 Hz, ArH);
7.12 (d, 4H, J = 8.5 Hz, ArH); 7.07 (d, 2H, J = 8.9 Hz, ArH); 6.87 (d, 2H, J = 8.9 Hz, ArH); 6.27
(s, 1H, OH); 4.03 (t, 2H, J = 6.2 Hz, OCH2); 2.87–2.79 (m, 6H, COCH2, COCH2CH2CO); 2.45
(s, 6H, CH3); 2.10–2.03 (m, 2H, CH2CH2CH2).
3-{4-[Hydroxy-bis(4-methoxyphenyl)methyl]phenyl}propionic acid, N-oxysulfosuccinimide
ester, sodium salt (16a) was prepared from 14a (0.96 g, 2.0 mmol) using the general procedure
for oxysulfosuccinimide esters. Yield 793 mg (67%), brown solid, Rf 0.54 (n-propanol–EtOAc–
water, 8:1:1).
3-{4-[Hydroxy-bis(4-methylthiophenyl)methyl]phenyl}propionic
acid,
N-
oxysulfosuccinimide ester, sodium salt (16b) was prepared from 14c (425 mg, 1.0 mmol).
Yield 412 mg (66%), white solid, Rf 0.58 (n-propanol–EtOAc–water, 8:1:1). ESI-TOF HRMS:
m/z = 606.0697 [M–OH]+, calc. for [C28H25NNaO7S3]+ 606.0685. NMR (DMSO-d6): 7.24–7.08
(m, 12H, ArH); 6.35 (s, 1H, OH); 3.94 (br., 1H, COCHS); 3.15 (br. s, 1H, COCHHCHS); 3.02–
2.83 (m, 5H, ArCH2CH2, COCHHCHS); 2.45 (s, 6H, SCH3).
N,N′-Bis(3-{4-[bis(4-methoxyphenyl)hydroxymethyl]phenyl}propionyl)ethylenediamine
(17c). The acid 14a (200 mg, 0.51 mmol) and HATU were dissolved in DMF (5 mL), following
DIEA (174 μL; 1.0 mmol) was added and the reaction mixture was left for 5 min at ambient
temperature. After that this solution was added by one portion into the solution of ethylene
diamine (16.7 μL; 0.25 mmol) in DMF (3 ml) and the reaction mixture was left for 1 h. TLC
showed completion of the reaction (Rf 0.21; 30% acetone in PhMe + 0.5% Et3N). The reaction
was diluted with ethylacetate (150 mL), washed with water (2×100 mL) and brine (100 mL).
Organic layer was dried over Na2SO4 and evaporated. The residue was separated by column
chromatography. The target product was obtained as white solid. Yield 186 mg (92%). ESI-TOF
HRMS: m/z = 791.3702 [M–OH]+, calc. for [C50H51N2O7]+ 791.3691. 1H NMR (DMSO-d6): 7.82

(m, 2H, NH); 7.09–7.05 (m, 16H, ArH); 6.84–6.80 (m, 8H, ArH); 6.12 (br.s, 2H, OH); 3.72 (s,
13
12H, OCH3); 3.04 (m, 4H), 2.79 (m, 4H), 2.34 (m, 4H) (CH2). C NMR (DMSO-d6): 171.50
(2C, CO), 157.83 (4C), 146.04 (2C), 140.41 (4C), 139.40 (2C), 128.92 (8C), 128.30, 128.21,
127.68 (2C), 127.26 (2C), 112.78 (8C), 79.82 (2C), 55.05 (4C), 38.37 (2C), 37.11, 37.03 (2C),
31.09, 30.67 (2C).
1,3,5-Tris[3-(2-{4-[bis(4-methoxyphenyl)hydroxymethyl]phenyl}ethylcarbonylamino)-
propylaminocarbonyl]benzene (17d). A solution of activated ester 15a (245 mg, 0.50 mmol) in
DCM (300 mL) was added dropwise to a solution of 1,3-diaminopropane (7.40 g, 100 mmol) in
DCM (300 mL) within 2 h and the mixture was stirred further for 2 h. The resulting solution was
washed with water (15×100 mL), dried over Na2SO4 and evaporated. The residue was dissolved
in DCM (10 mL) and trimesic chloride (26.5 mg, 0.1 mmol) was added in one portion. The
mixture was stirred for 6 h, after that it diluted with ethyl acetate (200 mL) and successively
washed with 5% NaHCO3 (2×100 mL) and water (2×100 mL). The organic layer was dried over
Na2SO4 and evaporated. The residue was cromatographed on silica gel (eluent PhMe–acetone
1:1 + 1% Et3N) to give target product as white solid. Yield 132 mg (88%). Rf 0.44 (acetone +
0.5% Et3N). ESI-TOF HRMS: m/z = 1483.6917 [M–OH]+, calc. for [C90H95N6O14]+ 1483.6901.
1H NMR ([D6]DMSO): 8.67 (t, 3H, J = 5.5 Hz, NH); 8.41 (s, 3H, ArH); 7.84 (t, 3H, J = 5.6 Hz,
NH); 7.13–7.04 (m, 24H, ArH); 6.82 (d, 12H, J = 8.9 Hz, ArH); 6.11 (br.s, 3H, OH); 3.26 (m,
6H), 3.10 (m, 6H) (NHCH2); 2.78 (t, 6H, J = 7.6 Hz, ArCH2); 2.36 (m, 6H, COCH2); 1.65 (m,
6H, NHCH2CH2). 13C NMR (DMSO-d6): 171.35 (3C, CO), 165.49 (3C, CO), 157.82 (6C),
146.02 (2C), 140.40 (C), 139.44 (C), 135.07, 128.91 (12C), 128.40, 127.69 (C), 127.26 (C),
112.77 (12C), 79.81 (3C), 68.55, 55.88, 55.02 (6C), 45.73, 37.25, 37.09, 36.44, 32.13, 30.78,
29.65, 29.19.
O
N I
O
O
O
MeCN
I
I
I
O
MeO
OMe
MeO
OMe
MeO
OMe
O
O
Pd(PPh3)4, CuI, Et3N
O
O
O
O
O
O
O
O
MeO
OMe
MeO
OMe
H2, Pd/C
EtOAc
NMe2
O
Me2N
MgBr
/ THF
HO
O
O
O
O
MeO
MeO
OMe
MeO
OMe
MgBr
/ THF
OMe
OMe
O
HO
HO
1. CF3CO2H/DCM
2. DSC/Et3N/DCM
O
O
O
N
O
O
MeO
OMe
MeO
OMe
4,4′-Dimethoxybenzophenone (2.42 g, 10 mmol) was iodinated with N-iodosuccinimide (2.24 g,
10 mmol) in boiling acetonitrile (200 mL) in the presence of trifluoroacetic acid (0.2 mL). After
5 h the mixture was cooled, evaporated, and neutralized with 5% NaHCO3. The residue was
dissolved in EtOAc (150 mL), washed with water (2×50 mL), dried over Na2SO4, evaporated
and chromatographed in toluene.
A
sample (140 mg) of 3,3′-diiodo-4,4′-

dimethoxybenzophenone was isolated. NMR (DMSO-d6): 8.10 (d, 2H, J2,6 = J2’,6’ = 2.0 Hz,
ArH); 7.74 (dd, 2H, J2,6 = J2’,6’ = 2.0 Hz, J5,6 = J5’,6’ = 8.5 Hz, ArH); 7.15 (d, 2H, J5,6 = J5’,6’ = 8.5
Hz, ArH); 3.94 (s, 6H, OCH3). The resulting mixture of 3-iodo-4,4’-dimethoxybenzophenone
and 3,3’-diiodo-4,4’-dimethoxybenzophenone (3.55 g) was dissolved in DMF (100 mL) and tert-
butyl 5-hexynoate (2.02 g, 12.0 mmol), triethylamine (3.34 mL, 24 mmol), Pd(PPh3)4 (925 mg,
0.8 mmol) and CuI (305 mg, 1.6 mmol) were added, and the reaction mixture was stirred for 24
h at room temperature. Then the mixture was diluted with EtOAc (400 mL), washed with 3%
aqueous EDTA-(NH4)2 (5×200 mL) and water (2×200 mL), dried, and evaporated to dryness.
The residue was chromatographed on a silica gel column (4.5×15 cm) in a 0→8% gradient of
EtOAc
in
toluene
to
give
3-[5-(tert-butyloxycarbonyl)pent-1-ynyl]-4,4′-
dimethoxybenzophenone (22a) (2.12 g, 52%). ESI-TOF HRMS: m/z = 423.2175 [M+H]+, calc.
for [C26H31O5]+ 423.2166. NMR (DMSO-d6): 7.72–7.67 (m, 3H, ArH); 7.64 (d, 1H, 4J = 2.3 Hz,
ArH); 7.17 (d, 1H, J = 8.7 Hz, ArH); 7.08 (d, 2H, J = 9.0 Hz, ArH); 3.91 (s, 3H, OCH3); 3.86 (s,
3H, OCH3); 2.47 (t, 2H, J = 7.0 Hz, ≡CCH2); 2.38 (t, 2H, J = 7.4 Hz, COCH2); 1.75 (m, 2H,
CH2CH2CH2); 1.39 (s, 9H, CCH3) and 3,3’-bis[5-(tert-butyloxycarbonyl)pent-1-ynyl]-4,4′-
4
dimethoxybenzophenone (1.26 g, 22%) NMR (DMSO-d6): 7.67 (dd, 2H, J = 8.7 Hz, J = 2.0
Hz, ArH); 7.64 (d, 2H, J = 2.0 Hz, ArH); 7.18 (d, 2H, J = 8.7 Hz, ArH); 3.91 (s, 6H, OCH3);
4
2.47 (t, 4H, J = 7.0 Hz, ≡CCH2); 2.37 (t, 4H, J = 7.4 Hz, COCH2); 1.75 (m, 2H, CH2CH2CH2);
1.39 (s, 18H, CCH3) as colourless oils.
CO2Me
OMe
CO2Me
CO2H
OMe
COCl
OMe
1. NaOH
2. HCl
I2/HNO3
SOCl2
I
I
I
OMe
anisole, I2
reflux
O
O
I2/HNO3
I
MeO
OMe
MeO
OMe
Methyl 3-iodo-4-methoxybenzoate. To a solution of methyl 4-methoxybenzoate (29.7 g, 0.18
mol) in CCl4 (110 mL) iodine (22.7 g, 0.89 mol) was added and the mixture was stirred for 10
min. Nitric acid (58%, 50 mL) was added dropwise wiwhin 30 min and the mixture was refluxed
for 3 h. The mixture was cooled to room temperature and precipitate formed was filtered off. The
organic layer was separated, washed with 5% Na2SO3 (100 mL), dried over CaCl2 and
evaporated. The residue was combined with the precipitate and recrystallized twice from EtOH.
Yield 30.4 g (58%).
3-Iodo-4-methoxybenzoyl chloride. Methyl 3-iodo-4-methoxybenzoate (29.2 g, 0.1 mol) was
suspended in EtOH (150 mL), the solution of NaOH (4.4 g, 0.11 mol) was added in one portion.
The mixture was stirred and heated at 40ºC overnight, then cooled, diluted with water (400 mL).
3-Iodo-4-methoxybenzoic acid was precipitated with conc. HCl, filtered off, washed with cold
water, and dried over P4O10. The acid was suspended in CHCl3 (150 mL), and SOCl2 (9.5 mL,
0.13 mmol) was added. The mixture was stirred overnight, then evaporated and the residue was
distilled under reduced pressure to give the desired acid chloride as a solid (mp ca. 50ºC, bp
145–150ºC/1 Torr). Yield 18.2 g (61%).
3-Iodo-4,4′-dimethoxybenzophenone (18). A. The mixture of 3-iodo-4-methoxybenzoyl
chloride (14.8 g, 0.05 mol), anisole (11.0 mL, 0.1 mol) and iodine (0.5 g) was refluxed for 10 h,
then cooled to 60ºC, diluted with iPrOH (200 mL), refluxed for 30 min, cooled and kept in

freezer overnight. The precipitate was filtered off, washed with cold iPrOH (10 mL), dried, and
recrystallized from EtOH. Yield 10.4 (56.5%), off-white solid. ESI-TOF HRMS: m/z = 383.0139
1
4
[M+H]+, calc. for [C16H16IO3]+ 383.0139. H NMR (DMSO-d6): 8.09 (d, J2,6 = 2.0 Hz, 1H; H-
2), 7.73 (dd, J5,6 = 8.7 Hz, 4J2,6 = 2.0 Hz, 1H; H-6), 7.70 (d, J2’,3’ = J5’,6’ = 8.7 Hz, 2H; H-2’,6’),
7.12 (d, J5,6 = 8.7 Hz, 1H; H-5), 7.07 (d, J2′,3′ = J5′,6′ = 8.7 Hz, 2H; H-3′,5′), 3.93 (s, 3H, 4-OCH3),
3.86 (s, 3H, 4′-OCH3). 13C NMR (DMSO-d6): 191.95 (CO), 162.80 (C-4′), 160.88 (C-4), 140.25
(C-2), 132.03 (C-6), 131.91 (2C, C-2′,6′), 131.85 (C-1), 129.55 (C-1′), 113.90 (2C, C-3′,5′),
110.90 (C-5), 86.15 (C-3), 56.87 (4-OCH3), 55.57 (4′-OCH3).
B. 4,4′-Dimethoxybenzophenone (18.1 g, 75 mmol) was dissolved in dioxane (70 mL) at 60ºC,
iodine (9.9 g, 39 mmol) was added and the mixture was stirred for 15 min. Water (20 mL) was
added, and 58% HNO3 (41 mL) was added dropwise within 2 h. The mixture was stirred at 60ºC
until iodine colouring disappears (ca. 6–7 h). The flask was evacuated to remove nitrogen oxides,
the mixture was diluted with water (100 mL), cooled, and the precipitate was filtered off, washed
with 5% NaHCO3 and water. The solid was suspended in EtOH (200 mL), refluxed for 15 min,
filtered hot, and cooled in freezer to 4ºC. The solid (16 g) was filtered off and dried. It contains
(GLC) 75% of desired 3-iodo-4,4′-dimethoxybenzophenone, 24% of starting 4,4′-
dimethoxybenzophenone and 0.7% of 3,3′-diiodo-4,4′-dimethoxybenzophenone. This was
purified by column chromatography in toluene. Yield 11.2 g (40%).
O
O
I
I2/HNO3
EtO
OEt
EtO
OEt
O
O
O
O
Pd(PPh3)4, CuI, Et3N
O
EtO
OEt
3-Iodo-4,4′-diethoxybenzophenone (20). 4,4′-Diethoxybenzophenone was iodinated according
to procedure for iodination of 4,4'-dimethoxybenzophenone. The resulting compound was
purified by column chromatography in toluene. Yield 36%. ESI-TOF HRMS: m/z = 411.0441
4
[M+H]+, calc. for [C18H20IO3]+ 411.0452. NMR (DMSO-d6): 8.08 (d, 1H, J2,6 = 2.0 Hz, H-2);
7.73–7.67 (m, 3H, H-2’,6,6’); 7.10 (d, 1H, J = 8.7 Hz, H-5); 7.06 (d, 2H, J = 8.7 Hz, H-3’,5’);
4.20 (q, 2H, J = 7.0 Hz), 4.13 (q, 2H, J = 7.0 Hz) (OCH2); 1.40 (t, 3H, J = 7.0 Hz), 1.36 (t, 2H, J
= 7.0 Hz) (CH3).
3-[5-(tert-Butyloxycarbonyl)pent-1-ynyl]-4,4′-diethoxybenzophenone (22b). To a solution of
3-iodo-4,4′-diethoxybenzophenone (4.54 g, 11.5 mmol) and tert-butyl 5-hexynoate (2.14 g, 12.7
mmol) in DMF (50 mL) Pd(PPh3)4 (1.40 g, 1.22 mmol), CuI (465 mg, 2.44 mmol), Et3N (3.2
mL, 23 mmol) were subsequently added. The mixture was stirred overnight under argon, then
diluted with water (200 mL) and extracted with EtOAc (200 mL). The organic layer was washed
with water (4×200 mL), 0.1 M solution (NH4)2EDTA (4×200 mL) and dried over Na2SO4. The
residue was chromatographed column in gradient of EtOAc in toluene (0→5%). Yield 4.53 g
(90%), viscous yellowish oil. ESI-TOF HRMS: m/z = 451.2494 [M+H]+, calc. for [C28H35O5]+
451.2479. NMR (DMSO-d6): 7.72–7.61 (m, 4H, H-2,2’,6,6’); 7.15 (d, 1H, J = 8.7 Hz, H-5); 7.06
(d, 2H, J = 8.7 Hz, H-3’,5’); 4.21–4.10 (m, 4H, OCH2); 2.47 (t, 2H, J = 6.6 Hz), 2.42 (t, 2H, J =
7.6 Hz) (CH2CH2CH2); 1.74 (m, 2H) (≡CH2CH2); 1.42–1.34 (m, 15H, CH3).

O
O
O
BnCl
MeONa/ HMPA
I
I
BBr3 / DCM
MeO
BnO
OMe
HO
O
OH
O
O
O
Pd(PPh3)4, CuI, Et3N
I
O
BnO
OBn
OBn
4,4′-Dihydroxy-3-iodobenzophenone (19). To
a
solution of 4,4′-dimethoxy-3-
iodobenzophenone (6.0 g, 16.3 mmol) in DCM (100 mL) boron tribromide (4.6 mL, 49.0 mmol)
was added in one portion. The mixture was stirred for 12 h. The progress of the reaction was
monitored by TLC (30% EtOAc in toluene). Then the mixture was poured in water (200 mL) and
the suspension was extracted with EtOAc (3×250 mL). The organic layer was dried with
Na2SO4, evaporated, and the residue was coevaporated with MeOH (3×100 mL). Yield 5.5 g
(99%), brownish solid. ESI-TOF HRMS: m/z = 354.9815 [M+H]+, calc. for [C14H12IO3]+
354.9826. NMR (DMSO-d6): 11.18 (br.s, 1H, OH); 10.32 (br.s, 1H, OH); 8.01 (d, 1H, 4J2,6 = 2.0
Hz, H-2); 7.63–7.55 (m, 3H, H-6,2’,6’); 6.98 (d, 1H, J = 8.4 Hz, H-5); 6.88 (d, 2H, J = 8.4 Hz,
H-3’,5’).
4,4′-Dibenzyloxy-3-iodobenzophenone (21). Sodium (0.46 g, 20 mmol) was dissolved in
MeOH and the resulting solution of MeONa was added to a solution of 4,4’-dihydroxy-3-
iodobenzophenone (3.40 g, 10 mmol) in methanol (50 mL). The mixture was evaporated to
dryness, the residue was dissolved in HMPA (30 mL) and benzyl chloride (2.78 g, 22 mmol) was
added in one portion. The mixture was heated at 80ºC for 5 h, then cooled, diluted with water
(200 mL) and extracted with EtOAc (2×150 mL). The combined organic layers were washed
with water (5×100 mL), dried over Na2SO4, and evaporated. The residue was chromatographed
on silica gel in 0→3% EtOAc in toluene to give the desired benzophenone (4.10 g, 79%). ESI-
TOF HRMS: m/z = 535.0752 [M+H]+, calc. for [C28H24IO3]+ 535.0765. NMR (DMSO-d6): 8.11
(d, 1H, 4J2,6 = 1.9 Hz, H-2); 7.76–7.58 (m, 3H, H-2′,6,6′); 7.53 (m, 2H), 7.48 (m, 2H), 7.42 (m,
4H), 7.35 (m, 2H) (ArH (phenyl)); 7.22 (d, 1H, J = 8.7 Hz, H-5); 7.17 (d, 2H, J = 8.7 Hz, H-
3′,5′); 5.32 (s, 2H), 5.22 (s, 2H) (OCH2).
3-[5-(tert-Butyloxycarbonyl)pent-1-ynyl]-4,4′-dibenzyloxybenzophenone (22c). To a solution
of 3-iodo-4,4′-dibenzyloxybenzophenone (4.50 g, 8.65 mmol) and tert-butyl 5-hexynoate (1.60
g, 9.51 mmol) in DMF (50 mL) Pd(PPh3)4 (1.00 g, 0.86 mmol), CuI (330 mg, 1.783 mmol), Et3N
(2.4 mL, 17 mmol) were subsequently added. The mixture was stirred overnight under argon,
then diluted with water (200 mL) and extracted with EtOAc (200 mL). The organic layer was
washed with water (4×200 mL), 0.1 M solution (NH4)2EDTA (4×200 mL) and dried over
Na2SO4. The residue was chromatographed column in gradient of EtOAc in toluene (0→10%).
Yield 4.10 g (84%), viscous yellowish oil. ESI-TOF HRMS: m/z = 575.2805 [M+H]+, calc. for
[C38H39O5]+ 575.2792. NMR (DMSO-d6): 7.75–7.65 (m, 4H, H-2,2′,6,6′); 7.49 (m, 4H), 7.41 (m,
4H), 7.35 (m, 2H) (ArH (phenyl)); 7.26 (d, 1H, J = 8.9 Hz, H-5); 7.16 (d, 2H, J = 8.9 Hz, H-
3′,5′); 5.30 (s, 2H), 5.22 (s, 2H) (OCH2); 2.48 (t, 2H, J = 6.9 Hz), 2.35 (t, 2H, J = 7.3 Hz)
(CH2CH2CH2); 1.75 (m, 2H) (≡CH2CH2); 1.38 (m, 9H, CH3).
3-[5-(tert-Butyloxycarbonyl)pentyl]-4,4′-(1,1′,2,2′-[13C])diethoxybenzophenone (23d). ESI-
TOF HRMS: m/z = 459.2941 [M+H]+, calc. for [C2413C4H39O5]+ 459.2926. NMR (DMSO-d6):
7.67 (d, 2H, J = 8.7 Hz, H-2′,6′); 7.55 (dd, 1H, 4J2,6 = 2.1 Hz, J = 8.3 Hz, H-6); 7.52 (d, 1H, J =
2.1 Hz, H-2); 7.05 (m, 3H, H-5,3′,5′); 4.13 (ddq, 4H, J = 6.8 Hz, 1JH,C = 145 Hz, 2JH,C = 2.5 Hz,
OCH2); 2.59 (t, 2H, J = 7.3 Hz, ArCH2); 2.17 (t, 2H, J = 7.3 Hz, COCH2); 1.59–1.45 (m, 7H,
COCH2CH2CH2CH2, OCH2CH3 (3H)); 1.36 (s, 9H, CCH3); 1.33–1.20 (m, 5H, COCH2CH2CH2,
OCH2CH3 (3H)).

O
O
O
O
Pd/C / H2
EtOAc
O
O
O
O
O
O
3-[5-(tert-Butyloxycarbonyl)pentyl]-4,4′-diethoxybenzophenone (23b). To a solution of 3-[5-
(tert-butyloxycarbonyl)pent-1-ynyl]-4,4′-diethoxybenzophenone (2.27 g, 5.20 mmol) in EtOAc
(100 mL) 10%Pd/C (500 mg) was added and the mixture was hydrogenated for 72 h at ambient
pressure. The mixture was filtered, evaporated and the residue was chromatographed on silica
gel (0 to 10% gradient of EtOAc in toluene) to give the desired compound as a viscous
colourless oil (1.92 g, 84%). ESI-TOF HRMS: m/z = 455.2778 [M+H]+, calc. for [C28H39O5]+
4
455.2792. NMR (DMSO-d6): 7.67 (d, 2H, J = 8.7 Hz, H-2′,6′); 7.55 (dd, 1H, J2,6 = 2.1 Hz, J =
8.6 Hz, H-6); 7.52 (d, 1H, J = 2.1 Hz, H-2); 7.05 (d, 1H, J = 8.6 Hz, H-5); 7.04 (d, 2H, J = 8.7
Hz, H-3′,5′); 4.16–4.10 (m, 4H, OCH2); 2.59 (t, 2H, J = 7.4 Hz, ArCH2); 2.17 (t, 2H, J = 7.0 Hz,
COCH2); 1.53 (m, 4H, COCH2CH2CH2CH2); 1.39–1.34 (m, 15H, CH3); 1.28 (m, 2H,
COCH2CH2CH2).
O
O
O
I
O
Pd(PPh3)4 / CuI
Et3N / DMF
O
O
O
O
O
+
O
3-[5-(tert-Butyloxycarbonyl)pent-1-ynyl]-4,4′-dibenzyloxybenzophenone (22c). To a solution
of 3-iodo-4,4′-dibenzyloxybenzophenone (4.50 g, 8.65 mmol) and tert-butyl 5-hexynoate (1.60
g, 9.51 mmol) in DMF (50 mL) Pd(PPh3)4 (1.00 g, 0.86 mmol), CuI (330 mg, 1.783 mmol), Et3N
(2.4 mL, 17 mmol) were subsequently added. The mixture was stirred overnight under argon,
then diluted with water (200 mL) and extracted with EtOAc (200 mL). The organic layer was
washed with water (4×200 mL), 0.1 M solution (NH4)2EDTA (4×200 mL) and dried over
Na2SO4. The residue was chromatographed column in gradient of EtOAc in toluene (0→10%).
Yield 4.10 g (84%), viscous yellowish oil. ESI-TOF HRMS: m/z = 575.2788 [M+H]+, calc. for
[C38H39O5]+ 575.2792. NMR (DMSO-d6): 7.75–7.65 (m, 4H, H-2,2′,6,6′); 7.49 (m, 4H), 7.41 (m,
4H), 7.35 (m, 2H) (ArH (phenyl)); 7.26 (d, 1H, J = 8.9 Hz, H-5); 7.16 (d, 2H, J = 8.9 Hz, H-
3′,5′); 5.30 (s, 2H), 5.22 (s, 2H) (OCH2); 2.48 (t, 2H, J = 6.9 Hz), 2.35 (t, 2H, J = 7.3 Hz)
(CH2CH2CH2); 1.75 (m, 2H) (≡CH2CH2); 1.38 (m, 9H, CH3).
O
O
O
O
O
Pd/C / H2
EtOAc
O
O
O
HO
OH
3-[5-(tert-Butyloxycarbonyl)pentyl]-4,4′-dihydroxybenzophenone (23c). To a solution of 3-
[5-(tert-butyloxycarbonyl)pent-1-ynyl]-4,4′-dibenzyloxybenzophenone (2.05 g, 3.66 mmol) in
EtOAc (100 mL) 10%Pd/C (500 mg) was added and the mixture was hydrogenated for 72 h at
ambient pressure. The mixture was filtered, evaporated and the residue was chromatographed on
silica gel (0 to 10% gradient of EtOAc in toluene) to give the desired compound as a viscous
colourless oil (1.03 g, 73%). ESI-TOF HRMS: m/z = 399.2177 [M+H]+, calc. for [C24H31O5]+
399.2166. NMR (DMSO-d6): 10.22 (s, 1H), 10.14 (s, 1H) (OH); 7.59 (d, 2H, J = 8.8 Hz, H-
2′,6′); 7.46 (d, 1H, J = 2.0 Hz, H-2); 7.41 (dd, 1H, 4J2,6 = 2.0 Hz, J = 8.7 Hz, H-6); 6.87 (m, 3H,
H-5,3′,5′); 2.55 (t, 2H, J = 7.6 Hz, ArCH2); 2.16 (t, 2H, J = 7.3 Hz, COCH2); 1.53 (m, 4H,
COCH2CH2CH2CH2); 1.36 (m, 9H, CH3); 1.30 (m, 2H, COCH2CH2CH2).

O
O
O
HO
OH
23c
OMe
O
O
HO
*
*
O
O
O
O
*
*
*
*
O
23d
O
O
*
*
24d
OMe
OMe
O
HO
HO
O
N
CO2H
*
*
*
*
O
O
O
*
*
O
O
O
*
*
SO3Na
25d
3-[5-(tert-Butyloxycarbonyl)pentyl]-4,4′-(1,1′,2,2′-[13C])-diethoxybenzophenone (23d). To a
27b
magnetically stirred solution of 3-[5-(tert-butyloxycarbonyl)pentyl]-4,4′-
dihydroxybenzophenone (1.00 g, 2.6 mmol), [13C]ethanol (400 mg) and triphenylphosphine
(1.36 g, 5.20 mmol) in dry THF (30 mL) DIAD (2.46 ml, 8.1 mmol) was added dropwise within
15 min. The reaction mixture was heated to 40–45ºC until starting benzophenone is consumed
according to TLC, then cooled to room temperature, diluted with EtOAc (250 mL), washed with
washed with 3% citric acid (150 mL) and water (2×100 mL), dried over Na2SO4 and evaporated.
The residue was purified by column chromatography on silica gel (elution 0→15% EtOAc in
toluene). Yield (490 g, 42%), colourless oil. ESI-TOF HRMS: m/z = 459.2931 [M+H]+, calc. for
[C2413C4H39O5]+ 459.2926. NMR (DMSO-d6): 7.68 (d, 2H, J = 8.7 Hz, H-2′,6′); 7.55 (dd, 1H,
4J2,6 = 2.0 Hz, J = 8.2 Hz, H-6); 7.52 (d, 1H, J = 2.0 Hz, H-2); 7.07–7.02 (m, 3H, H-5, H-3′,5′);
4.13 (app. ddq, 4H, 1JH,C = 141.0 Hz, J = 6.8 Hz, 2JH,C = 2.5 Hz, [13C]CH2); 2.59 (t, 2H, J = 7.3
Hz, ArCH2); 2.17 (t, 2H, J = 7.3 Hz, COCH2); 1.58–1.45 (m, 7H, COCH2CH2CH2CH2,
[13C]CH3); 1.36 (s, 9H, CH3); 1.33–1.19 (m, 5H, COCH2CH2CH2, [13C]CH3).
6-{2-(1,2-[13C])Ethoxy-5-[hydroxy-(4-(1,2-[13C])ethoxyphenyl)-(4-methoxyphenyl)-
methyl]phenyl}hexanoic acid, tert-butyl ester (24d). To a stirred solution of 3-[5-(tert-
butyloxycarbonyl)pentyl]-4,4′-(1,1′,2,2′-[13C])-diethoxybenzophenone (470 mg; 1.06 mmol) in
dry THF (10 mL) 0.5 M 4-methoxyphenylmagnesium bromide (2.53 mL, 1.27 mmol) was added
in one portion under argon, and the mixture was stirred at ambient temperature overnight
(monitoring by TLC in EtOAc–toluene 1:3). After the disappearance of the starting ketone the
reaction was diluted with water (100 mL) and saturated aq. NH4Cl (50 mL), and extracted with
EtOAc (2×100 mL). The organic phase was dried over Na2SO4, evaporated, and
chromatographed on silica gel in 0→6% EtOAc in toluene with 0.5% of Et3N to give the desired
compound as a colourless oil. Yield 351 g (60%). ESI-TOF HRMS: m/z = 503.3355 [M–OH]+,
calc. for [C3013C4H43O3]+ 503.3341. NMR (DMSO-d6): 7.06 (m, 4H, ArH); 6.97 (d, 1H, 4J = 2.1
1
Hz, ArH); 6.81 (m, 6H, ArH); 6.00 (s, 1H, OH); 3.98 (app. ddq, 4H, JH,C = 139.5 Hz, J = 6.9
Hz, 2JH,C = 2.5 Hz, [13C]CH2); 3.72 (s, 3H, OCH3); 2.45 (t, 2H, J = 7.3 Hz, ArCH2); 2.13 (t, 2H,
J = 7.3 Hz, COCH2); 1.50–1.40 (m, 7H, COCH2CH2CH2CH2, [13C]CH3); 1.37 (s, 9H, t-Bu);
1.25–1.13 (m, 5H, COCH2CH2CH2, [13C]CH3).
6-{2-(1,2-[13C])Ethoxy-5-[hydroxy-(4-(1,2-[13C])ethoxyphenyl)-(4-methoxyphenyl)-methyl]-
phenyl}hexanoic acid, sulphosuccinimide ester (27b). To a stirred solution of tert-butyl ester
of
methyl]phenyl}hexanoic acid (271 mg; 0.5 mmol) in dry DCM (1 mL) trifluoroacetic acid (1
6-{2-(1,2-[13C])ethoxy-5-[hydroxy-(4-(1,2-[13C])ethoxyphenyl)-(4-methoxyphenyl)-

mL) was added in one portion and the mixture was stirred at ambient temperature for 3 h, then
evaporated, and co-evaporated with DCM (3×10 mL) to give the acid. The residue was
chromatographed on silica gel in 0→25% acetone in toluene to give the desired compound as a
yellowish oil, 30 mg (12% yield). It was dissolved in dry DMF (0.5 mL), then N-
oxysulfosuccinimide sodium salt (13 mg, 0.06 mmol) and DCC (19 mg, 0.09 mmol) were added
and the mixture was left under stirring overnight, then cooled to +4ºC and stirred for 2 h, and the
precipitate formed was filtered off. The solution was diluted with EtOAc (6 mL), cooled to +4ºC
overnight, filtered, and diluted with dry Et2O (50 mL). The mixture was kept at ambient
temperature for 2-3 h and the desired compound was collected by filtration, washed with ether
and dried in vacuo. Yield 41 mg (98%), white solid. ESI-TOF HRMS: m/z = 544.2891 [M–
OH]+, calc. for [C3013C4H38NO5]+ 544.2879. NMR (DMSO-d6): 7.05 (m, 4H, ArH); 6.97 (d, 1H,
4J = 2.0 Hz, ArH); 6.81 (m, 6H, ArH); 6.00 (s, 1H, OH); 3.98 (app. ddq, 4H, 1JH,C = 138.8 Hz, J
= 6.9 Hz, 2JH,C = 2.0 Hz, [13C]CH2); 3.94 (br., 1H, COCHS); 3.72 (s, 3H, OCH3); 3.15 (br. s, 1H,
COCHHCHS); 2.86 (m, 1H, COCHHCHS); 2.45 (t, 2H, J = 7.3 Hz, ArCH2); 2.15 (t, 2H, J = 7.3
Hz, COCH2); 1.50–1.40 (m, 7H, COCH2CH2CH2CH2, [13C]CH3); 1.25–1.13 (m, 5H,
COCH2CH2CH2, [13C]CH3).
Amides 28a-h were prepared using procedure similar to used for amides 10. The compounds
were chromatographed in 30% EtOAc in toluene + 0.5% Et3N. The following compounds were
obtained:
N-Octyl-6-{2-methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}hexanamide (28d),
yellowish oil, yield 90%. ESI-TOF HRMS: m/z = 574.3535 [M–OH]+, calc. for [C36H48NO5]+
574.3527. NMR (DMSO-d6): 7.65 (t, 1H, J = 5.4 Hz, NH); 7.06 (d, 4H, J = 8.9 Hz, ArH, H-
4
4
2’,6’); 6.98 (d, 1H, J = 2.3 Hz, ArH, H-6); 6.85 (dd, 1H, J = 8.5 Hz, J = 2.3 Hz, ArH, H-4);
6.82 (d, 4H, J = 8.9 Hz, ArH, H-3′,5′); 6.80 (m, 1H, H-3); 6.01 (s, 1H, OH); 3.74 (s, 3H), 3.72 (s,
6H) (OCH3); 2.99 (m, 2H, NCH2); 2.44 (t, 2H, J = 7.6 Hz, COCH2CH2CH2CH2CH2), 1.99 (t,
2H, J = 7.3 Hz, COCH2); 1.42 (m, 4H), 1.35 (m, 2H), 1.29–1.15 (m, 12H), (COCH2CH2CH2CH2,
NCH2CH2CH2CH2CH2CH2CH2); 0.85 (t, 3H, J = 6.9 Hz, CCH3).
N-Nonyl-6-{2-methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}hexanamide (28e),
yellowish oil, yield 96%. ESI-TOF HRMS: m/z = 588.3675 [M–OH]+, calc. for [C37H50NO5]+
588.3684. NMR (DMSO-d6): 7.65 (t, 1H, J = 5.4 Hz, NH); 7.07 (d, 4H, J = 8.7 Hz, ArH, H-
4
4
2’,6’); 6.98 (d, 1H, J = 2.2 Hz, ArH, H-6); 6.85 (dd, 1H, J = 8.5 Hz, J = 2.2 Hz, ArH, H-4);
6.82 (d, 4H, J = 8.7 Hz, ArH, H-3′,5′); 6.80 (m, 1H, H-3); 6.02 (s, 1H, OH); 3.74 (s, 3H), 3.72 (s,
6H) (OCH3); 2.99 (m, 2H, NCH2); 2.44 (t, 2H, J = 7.6 Hz, COCH2CH2CH2CH2CH2), 1.99 (t,
2H, J = 7.5 Hz, COCH2); 1.44 (m, 4H), 1.35 (m, 2H), 1.29–1.15 (m, 14H), (COCH2CH2CH2CH2,
NCH2CH2CH2CH2CH2CH2CH2CH2); 0.84 (t, 3H, J = 6.9 Hz, CCH3).
N-Decyl-6-{2-methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}hexanamide (28f),
yellowish oil, yield 100%. ESI-TOF HRMS: m/z = 602.3830 [M–OH]+, calc. for [C38H52NO5]+
602.3840. NMR (DMSO-d6): 7.65 (t, 1H, J = 5.5 Hz, NH); 7.07 (d, 4H, J = 8.7 Hz, ArH, H-
4
4
2′,6′); 6.98 (d, 1H, J = 2.1 Hz, ArH, H-6); 6.86 (dd, 1H, J = 8.5 Hz, J = 2.1 Hz, ArH, H-4);
6.82 (d, 4H, J = 8.7 Hz, ArH, H-3′,5′); 6.80 (m, 1H, H-3); 6.01 (s, 1H, OH); 3.74 (s, 3H), 3.72 (s,
6H) (OCH3); 2.99 (m, 2H, NCH2); 2.44 (t, 2H, J = 7.6 Hz, COCH2CH2CH2CH2CH2), 1.99 (t,
2H, J = 7.3 Hz, COCH2); 1.45 (m, 4H), 1.35 (m, 2H), 1.29–1.15 (m, 16H), (COCH2CH2CH2CH2,
NCH2CH2CH2CH2CH2CH2CH2CH2CH2); 0.84 (t, 3H, J = 6.9 Hz, CCH3).
N-(2-Phenylethyl)-6-{2-methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}-
hexanamide (28g), yellowish oil, 93% yield. ESI-TOF HRMS: m/z = 566.2909 [M–OH]+, calc.
for [C36H40NO5]+ 566.2901. NMR (DMSO-d6): 7.78 (t, 1H, J = 5.5 Hz, NH); 7.26 (m, 2H, ArH,
H-3′′,5′′); 7.17 (m, 3H, ArH, H-2′′,4′′,6′′); 7.07 (d, 4H, J = 8.9 Hz, ArH, H-2′,6′); 6.99 (d, 1H, 4J
= 2.1 Hz, ArH, H-6); 6.86 (dd, 1H, J = 8.5 Hz, 4J = 2.1 Hz, ArH, H-4); 6.82 (d, 4H, J = 8.9 Hz,
ArH, H-3’,5’); 6.80 (m, 1H, H-3); 6.02 (s, 1H, OH); 3.75 (s, 3H), 3.72 (s, 6H) (OCH3); 3.24 (m,
2H, NCH2); 2.68 (t, 2H, J = 7.3 Hz, COCH2CH2CH2CH2CH2), 2.44 (t, 2H, J = 7.5 Hz,

NCH2CH2); 1.99 (t, 2H, J = 7.4 Hz, COCH2); 1.42 (m, 4H, COCH2CH2CH2CH2); 1.17 (m, 2H,
COCH2CH2CH2).
N-(3-Phenylpropyl)-6-{2-methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}-
hexanamide (28h), yellowish oil 90% yield. ESI-TOF HRMS: m/z = 580.3043 [M–OH]+, calc.
for [C37H42NO5]+ 580.3057. NMR (DMSO-d6): 7.73 (t, 1H, J = 5.5 Hz, NH); 7.26 (m, 2H, ArH,
H-3′′,5′′); 7.17 (m, 3H, ArH, H-2′′,4′′,6′′); 7.06 (d, 4H, J = 8.9 Hz, ArH, H-2′,6′); 6.99 (d, 1H, 4J
= 2.0 Hz, ArH, H-6); 6.85 (dd, 1H, J = 8.6 Hz, 4J = 2.0 Hz, ArH, H-4); 6.82 (d, 4H, J = 8.9 Hz,
ArH, H-3′,5′); 6.80 (d, 1H, J = 8.6 Hz, ArH, H-3); 6.02 (s, 1H, OH); 3.73 (s, 3H), 3.72 (s, 6H)
(OCH3); 3.03 (m, 2H, NCH2); 2.55 (t, 2H, J = 7.8 Hz, COCH2CH2CH2CH2CH2), 2.45 (t, 2H, J =
7.4 Hz, NCH2CH2CH2); 2.02 (t, 2H, J = 7.3 Hz, COCH2); 1.67 (m, 2H, NCH2CH2); 1.45 (m, 4H,
COCH2CH2CH2CH2); 1.21 (m, 2H, COCH2CH2CH2).
OMe
MeO
MgBr
O
O
CF3CO2H/DCM
O
HO
O
O
MeO
OMe
OMe
MeO
OMe
22a
29
OMe
O
DSC/Et3N/DCM
HO
CO2H
O
HO
N
O
O
MeO
OMe
MeO
OMe
30
31
6-{2-Methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}-5-hexynoic acid, tert-butyl
ester (29). To a stirred solution 3-[5-(tert-butyloxycarbonyl)pent-1-ynyl]-4,4′-dimethoxy
benzophenone (1.18 g; 2.88 mmol) in dry THF (20 mL) 0.9 M 4-methoxyphenylmagnesium
bromide (5.8 mL, 4.0 mmol) was added in one portion under argon, and the mixture was kept at
ambient temperature overnight (monitoring by TLC in EtOAc–toluene 1:3). The reaction was
diluted with water (50 mL) and 5% citric acid (15 mL), and extracted with EtOAc (100 mL). The
organic phase was dried over Na2SO4, evaporated, and chromatographed on silica gel in 0→5%
EtOAc in toluene with 1% of Et3N to give the desired compound as a colourless oil. Yield 516
mg (35%). ESI-TOF HRMS: m/z = 499.2474 [M–OH]+, calc. for [C32H35O5]+ 499.2479. NMR
4
(DMSO-d6): 7.12 (d, 1H, J = 2.1 Hz, ArH); 7.09–7.02 (m, 5H, ArH); 6.92 (d, 1H, J = 8.9 Hz,
ArH); 6.84 (d, 4H, J = 8.9 Hz, ArH); 6.16 (s, 1H, OH); 3.78 (s, 3H), 3.73 (s, 6H) (OCH3); 2.40
(t, 2H, J = 7.0 Hz, ≡CCH2); 2.33 (t, 2H, J = 7.5 Hz, COCH2); 1.70 (m, 2H, CH2CH2CH2); 1.39
(s, 9H, CCH3).
6-{2-Methoxy-5-[hydroxy-bis(4-methoxyphenyl)methyl]phenyl}-5-hexynoic
acid,
N-
oxysuccinimide ester (31). To a stirred solution of tert-butyl ester of 6-{2-methoxy-5-[hydroxy-
bis(4-methoxyphenyl)methyl]phenyl}-5-hexynoic acid (516 mg; 1.0 mmol) in dry DCM (3.5
mL) trifluoroacetic acid (3.5 mL) was added in one portion and the mixture was stirred at
ambient temperature for 5 h, then evaporated, and co-evaporated with DCM (4×20 mL) to give
free acid. Product were dissolved in DCM (10 mL), and triethylamine (0.42 mL, 3.0 mmol) and
N,N-disuccinimidyl carbonate (384 mg, 1.5 mmol) were added and the mixture was stirred
overnight, then evaporated, dissolved in EtOAc (50 mL), washed with 5% NaHCO3 (50 mL) and
water (50 mL), dried over Na2SO4, evaporated, and the residue was purified by column
chromatography (5→10% acetone in toluene). Yield 218 mg (39%), white amorphous solid.
ESI-TOF HRMS: m/z = 540.2022 [M–OH]+, calc. for [C32H30NO7]+ 540.2017. NMR (DMSO-
d6): 7.14 (d, 1H, 4J = 2.1 Hz, ArH); 7.09–7.02 (m, 5H, ArH); 6.93 (d, 1H, J = 8.8 Hz, ArH); 6.84
(d, 4H, J = 8.7 Hz, ArH); 6.17 (s, 1H, OH); 3.79 (s, 3H), 3.73 (s, 6H) (OCH3); 2.81 (m, 6H,
COCH2, COCH2CH2CO); 2.51 (t, 2H, J = 7.0 Hz, ≡CCH2); 1.86 (m, 2H, CH2CH2CH2).

O
O
O
O
MeO
OMe
O
MeO
O
OTf
MeO
O
OH
35
34
O
33
OMe
HO
HO
O
O
MeO
O
MeO
O
OH
O
37
36
OMe
OMe
HO
HO
O
O
O
O
N
MeO
O
O
MeO
O
N
O
O
39
38
O
3-Methoxy-9-oxo-9H-xanthen-6-yl trifluoromethanesulfonate (34). To a ice cooled solution
of 6-hydroxy-3-methoxy-9H-xanthen-9-one (0.70 g, 0.29 mmol) in dry pyridine (40 mL)
trifluoromethanesulphonic anhydride (0.90 g, 0.32 mmol) was added dropwise within 1 h and the
reaction was left overnight at room temperature, then poured into 5 % HCl (150 mL), and the
product was extracted with dichloromethane (2×100 mL). The solution was dried over anhydrous
sodium sulphate, filtered and concentrated in vacuo to give the desired product, 0.86 g (79.3 %).
1
ESI-TOF HRMS: m/z = 375.0151 [M+H]+, calc. for [C15H10F3O6S]+ 375.0145. H NMR
(400MHz, CDCl3) δ 8.43 (d, J = 8.8 Hz, 1H), 8.28 (d, J = 8.9 Hz, 1H), 7.45 (s, 1H), 7.30 ((d, J =
11.2 Hz, 1H), 7 (d, J = 11.3 Hz, 1H), 6.9 (s, 1H), 4 (s, 3H).
tert-Butyl 6-(3-methoxy-9-oxo-9H-xanthen-6-yl)hex-5-ynoate (35) was prepared as described
for ketones 22 from triflate 34 (0.864, 2.30 mmol), tert butyl 5-hexynoate (1.55 g, 9.23 mmol),
Pd(PPh3)2Cl2 (0.162 g, 0.230 mmol), CuI (0.0439 g, 0.230 mmol), and DIEA (1.61 mL, 9.2
mmol). The product was purified by column chromatography, hexane–ethyl acetate, gradient
elution (7:1); yield 0.753 g (83 %). ESI-TOF HRMS: m/z = 393.1689 [M+H]+, calc. for
[C24H25O5]+ 393.1697. 1H NMR (400MHz, CDCl3) δ 8.2 (dd, J = 8.2, 8.9 Hz, 2H), 7.5 (s, 1H), 7
(dd, J = 8.8, 8.9 Hz, 2H), 6.9 (s, 1H), 4 (s, 3H), 2.6 (t, 2H), 2.4 (t, 2H), 1.9 (t, 2H), 1.5 (s, 9H).
tert-Butyl
6-(9-hydroxy-3-methoxy-9-(4-methoxyphenyl)-9H-xanthen-6-yl)hex-5-ynoate
(36) was prepared from ketone 35 (0.720 g, 1.83 mmol) and 4-methoxyphenyl magnesium
bromide (0.5 M solution in THF, 7.35 mL, 3.66 mmol) in THF (30 mL). After usual workup the
product was purified by column chromatography, hexane–ethyl acetate (4:1), gradient elution;
(0.52 g, 57 % yield). ESI-TOF HRMS: m/z = 483.2173 [M–OH]+, calc. for [C31H31O5]+
1
483.2166. H NMR (400MHz, CDCl3) δ 7.2 (m, 5H), 7.1 (d, J = 8.1 Hz, 2H), 7.4 (m, 1H), 6.6
(m, 2H), 3.8 (s, 3H), 3.78 (s, 3H), 2.5 (t, 2H), 2.4 (t, 2H), 1.9 (t, 2H), 1.4 (s, 9H).
6-(9-Hydroxy-3-methoxy-9-(4-methoxyphenyl)-9H-xanthen-6-yl)hex-5-ynoic acid (37) was
prepared using general procedure for compounds 6 from ester 36 (0.520 g, 1.04 mmol). Yield
0.461 g (100 %).
6-(9-Hydroxy-3-methoxy-9-(4-methoxyphenyl)-9H-xanthen-6-yl)hex-5-ynoate-N-
hydroxysuccinimide (38) was prepared using usual procedure from acid 37 (0.461, 1.04 mmol).
Yield 0.561 g (100 %). ESI-TOF HRMS: m/z = 524.1702 [M–OH]+, calc. for [C31H27NO7]+