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S. Machida et al. / Bioorg. Med. Chem. 21 (2013) 4004–4010
dichlromethane (20 mL) was added the acid chloride in dichloro-
methane (10 mL), and the mixture was refluxed for 1 h. After cool-
ing to rt, to the solution was added triethylamine (3.5 mL, 25 mmol)
in toluene (32 mL) and boron trifuoride diethyl ether (3.1 mL,
25 mmol), then stirred at 50 °C for 1 h. The product was extrated
with dichloromethane, and purified by SiO2 column chromatogra-
phy to give 4,4-difluoro-8-(butyl-4-carboxybenzyl)-1,3,5,7-tetra-
4.1.2.4. N-(5-[3,4,5-Tris{3-{1,3-diaminopropyl)-1-propanoxyl}}
benzoylamino]hexanylcarbonyl)-4-{N-[2(R)-amino-3-mercapto
propyl}-aminobenzoyl]-methionine methyl ester (3). Com-
pound 6 (40 mg, 0.022 mmol) was treated with 50% of trifluoroace-
tic acid and 5% triethylsilane in dichloromethane at 30 °C. The
reaction was monitored by HPLC until the starting material disap-
peared. The crude material was purified by preparative HPLC to
give the desired product as a white solid, 10 mg, 27%. 1H NMR
(400 MHz, DMSO-d6), d 1.29 (m, 2H, CH2CH2CH2CO), 1.51 (m, 4H,
CONHCH2CH2CH2CH2), 1.80–1.89 (6H, 3,4,5-CH2CH2, b-CH Val,
and b-CH2 Met), 2.03–2.13 (8H, 3,4,5-CHCH2, b-CH2 Met, and
SCH3), 2.66 (1H, CH2aSH), 2.60–2.78 (m, 2H, b-CH Cys), 3.00–3.07
(m, 12H, 3,4,5-CHCH2), 3.62 (s, 3H, CO2CH3), 3.94-4.07 (6H, 3,4,5-
methyl-4-bora-3a,4a-diaza-s-indacene as
a green amorphous
solid, 904 mg, 47%. 1H NMR (400 MHz, CDCl3) d. 2.41 (s, 6H, CH3-
dipyrrin), 2.51 (s, 6H, CH3-dipyrrin), 2.62-2.67 (m, 2H, CH2CO2Bn),
3.29-3.34 (m, 2H, CCH2), 5.17(s, 2H, CH2Ph), 6.05 (s, 2H, CH-dipyr-
rin), and 7.32–7.39 ppm (m, 5H, aromatic from benzyl): LRMS-ESI
(m/z): [M+Na]+ Calcd for C23H25BF2N2NaO2, 433. Found 433.
The benzyl ester (112 mg, 0.27 mmol) was removed by hydro-
genation with Pd(OH)2 (10 mg) in MeOH to give the desired prod-
uct as a red oil (96 mg, 99%). 1H NMR (400 MHz, CDCl3) d. 2.45 (s,
6H, CH3-dipyrrin), 2.52 (s, 6H, CH3-dipyrrin), 2.64–2.69 (m, 2H,
CH2CO2Bn), 3.31–3.35 (m, 2H, CCH2), and 6.08 ppm (s, 2H, CH-
dipyrrin).
OCH2,
a-CH), 4.51 (m, 1H, a-CH Met), 6.25 (br s, 1H, CH2CONH),
6.63 (d, 2H, J = 7.1 Hz, aromatic) 7.20 (s, 2H, aromatic from gallate),
7.64 (d, 2H, J = 8.0 Hz, aromatic), 7.77 (d, 1H, J = 7.1 Hz, CONH),
+
8.00 (br s, 18H, 3,4,5-CH2NH3 ꢀ6), 8.27 (1H, CONH), and
8.38 ppm (1H, CONH), LRMS-FAB (m/z): [M+H]+ Calcd for
C44H77N10O8S2, 937.5; found; 937.5, LRMS-FAB (m/z): [M+H]+ Calcd
for C44H77N10NaO8S2, 959.5187. Found; 959.5179.
4.1.2.2. N-(5-[3,4,5-Tris{3-{1,3-(N,N0-t-botoxycarbonyl)diamino
propyl)-1-propanoxyl}}benzoylamino]hexanylcarbonyl)-4-{N-
[2(R)-amino-3-(triphenyl-methyl)thio]propyl}-aminobenzoyl]-
methionine methyl ester (6). Compound 4 (113 mg, 0.096 mmol)
was coupled with peptidomimetic 5 (0.12 mmol) using PyBOP
(81 mg, 0.16 mmol), HOBt (31 mg, 0.20 mmol), and DIEA
(0.20 mmol) in DMF (3 mL). The crude product was purified by silica
gel column chromatography to give the desired product as colorless
solid, 125 mg, 73%. 1H NMR (400 MHz, CDCl3) d 1.43 (s, 54H,
CH2CH2CH2CONH, Boc ꢀ 6), 1.58–1.84 (m, 13H, 3,4,5-CH2CH,
4.1.2.5. N-[3,4,5-Tris[3-{1,3-(N,N0-tert-butoxycarbonyl)diamino-
propyl}-1-propanoxyl]benzoyl-
L-lysine benzyl ester (8).
A
solution of compound 7 (119 mg, 0.11 mmol), H-Lys(Fmoc)-OBn
tosylate (119 mg, 0.18 mmol), HOBt (34 mg, 0.22 mmol), PyBOP
(90 mg, 0.17 mmol), and DIEA (0.55 mmol) in DMF (1 mL) was stir-
red at rt for 3 h. After removal of DMF under the reduced pressure,
the product was extracted with AcOEt and 10% ctric acid. The or-
ganic layer was washed with Sat. NaHCO3, brine, and dried (anhyd.
Na2SO4). The crude material was purified by SiO2 column chroma-
tography (AcOEt / hexanes = 2/3 to 1/1) to give the product as a
colorless amorphous solid, 113 mg, 67%. 1H NMR (400 MHz, CDCl3)
CH2CH2CO, NHCH2CH2), 2.01–2.15 (m, 6H, SCH3, c-CH2 Met, and b-
CHa Met), 2.19–2.28 (m, b-CHb Met), 2.44 (dd, 1H J = 5.3 and
12.5 Hz, b-CHa Cys), 2.51–2.59 (m, 3H, –CHb Cys, CH2CONH), 3.05–
3.20 (m, 14H, 3,4,5-CH2NHBoc, and CH2NHPh), 3.32–3.39 (m, 2H,
d 1.43–1.47 (58H, Boc ꢀ 6,
c, d-CH2 Lys), 1.69–1.85 (9H, 3,4,5-
CHCH2), 1.96–2.00 (m, 1H, b-CHa Lys), 2.08–2.12 (m, 1H, b-CHb
CONHCH2), 3.75 (s, 3H, CO2CH3), 4.04–4.09 (3,4,5-OCH2,
a-CH Cys,
Lys), 3.07–3.16 (14H, 3,4,5-CH2NHBoc, and CH2NHFmoc Lys),
and NHPh), 4.83–4.88 (m, 1H, -CH Cys), 5.58–5.65 (m, 7H,
a
4.04–4.16 (7H, 3,4,5-OCH2, FmocCH), 4.85 (m, 1H, a-CH Lys), 5.00
NHBoc ꢀ 6, and CH2NHCO), 6.46 (d, 2H, J = 8.6 Hz, aromatic ring
from benzoyl), 6.82 (m, 1H, CONHCH2), 6.95 (m, 1H, NH Met), 7.05
(s, 2H, aromatic from gallate), 7.20–7.41 (m, 15H, aromatic from
Trt), and 7.58 ppm (d, 2H, J = 8.5 Hz, aromatic from benzoyl):
LRMS-ESI (m/z): [M+H]+ Calcd for C93H138N10NaO20S2, 1802.9.
Found; 1802.8.
(t, 1H, J = 4.8 Hz, NHFmoc), 5.18 (d, 1H, J = 12.2 Hz, CH2aPh), 5.22
(d, 1H, J = 12.2 Hz, CH2bPh), 5.43–5.81 (6H, 3,4,5-NHBoc), 6.96 (d,
1H, J = 7.0 Hz, PhCONH), 7.06 (s, 2H, aromatic form gallate), 7.26–
7.39 (m, 9H, aromatic from Fmoc and Benzyl), 7.54 (d, 2H.
J = 7.5 Hz, aromatic from Fmoc), and 7.73 ppm (d, 2H, J = 7.6 Hz,
aromatic from Fmoc).
4.1.2.3. N-(5-[3,4,5-Tris{3-{1,3-diaminopropyl)-1-propanoxyl}}
benzoylamino]hexanylcarbonyl)-4-{N-[2(R)-amino-3-mercapto
4.1.2.6. N-[3,4,5-Tris[3-{1,3-(N,N0-tert-butoxycarbonyl)diamino-
propyl}-1-propanoxyl]benzoyl-
L-lysine (9).
Compound
8
propyl}-aminobenzoyl]-methionine TFA salt (2).
6 (22 mg, 0.013 mmol) was hydrolyzed with 2 M KOH (200
Compound
L) in
(102 mg, 0.067 mmol) was treated with 20% diethylamine in
DMF for 1 h. Immediately after concentration, the product was
used for the next reaction without further purification.
l
MeOH (1.5 mL) under reflux condition for 1 h. The solution was
acidified with 10% citric acid, and the resulting free carboxylic acid
was extracted with dichloromethane, and the protecting groups
were then removed by 30% trifluoroacetic acid in dichloromethane
in the presence of 5% triethylsilane. The crude material was puri-
fied by preparative HPLC to give the desired product as colorless
solid, 14 mg, 70%. 1H NMR (400 MHz, DMSO-d6), d 1.28 (m, 2H,
CH2CH2CH2CO), 1.50 (m, 4H, CONHCH2CH2CH2CH2), 1.80–1.88
(6H, 3,4,5-CH2CH2, b-CH Val, and b-CH2 Met), 2.01–2.10 (8H,
4.1.2.7. N-[3,4,5-Tris[3-{1,3-(N,N0-tert-butoxycarbonyl)diamino-
propyl}-1-propanoxyl]benzoyl-N’(BODIPY-PEG4)-L-lysine benzyl
ester (10). A solution of compound 9 (0.067 mmol), BODIPY
(30 mg, 0.093 mmol), HOBt (24 mg, 0.16 mmol), PyBOP (54 mg,
0.10 mmol), and DIEA (0.15 mmol) in DMF (3 mL) was stirred for
18 h. After work up the reaction, the crude material was purified
by SiO2 column chromatography (chloroform/MeOH = 50/1) to give
the product as a red solid, 106 mg, 99%. 1H NMR (400 MHz, CDCl3) d.
3,4,5-CHCH2, b-CH2 and Met, SCH3), 2.26–2.31 (m, 2H,
Met), 2.62–2.73 (m, 2H, CH2SH), 2.60–2.78 (m, 2H, b-CH Cys),
3.00 (12H, 3,4,5-CHCH2), 3.92-4.05 (6H, 3,4,5-OCH2, -CH), 4.44
(m, 1H, -CH Met), 6.26 (br s, 1H, CH2CONH), 6.61 (d, 2H,
c-CH2
1.43 (58H, Bocꢀ6,
c, d-CH2 Lys), 1.69–1.96 (11H, 3,4,5-CHCH2, b-CH2
Lys), 2.37–2.43 (8H, BODIPY-CH2, CH3-dipyrrinꢀ2), 2.49 (s, 6H, CH3-
dipyrrin ꢀ 2), 3.05-3.25 (16H, 3,4,5-CH2NHBoc, BODIPY-CHCH2 and
a
a
J = 8.2 Hz, aromatic) 7.21 (s, 2H, aromatic from gallate), 7.65 (d,
e-CH2 Lys), 4.04 (br, 6H, 3,4,5-OCH2), 4.81 (m, 1H, a-CH Lys), 5.18 (d,
2H, J = 8.8 Hz, aromatic), 7.77 (d, 1H, J = 7.1 Hz, CONH), 8.03–8.15
1H, J = 12.2 Hz, CH2aPh), 5.22 (d, 1H, J = 12.2 Hz, CH2bPh), 5.57 (br s,
6H, 3,4,5-NHBoc), 6.00 (s, 2H, CH-dipyrrin), 6.83 (d, 1H, J = 7.5 Hz,
PhCONH), 6.98 (s, 2H, aromatic form gallate), and 7.32-7.36 ppm
(m, 5H, aromatic from Benzyl): LRMS-ESI (m/z): [M+Na]+ Calcd for
+
(br s, 19H, 3,4,5-CH2NH3 ꢀ 6, and CONH), and 8.41 ppm (1H,
CONH): LRMS-FAB (m/z): [M+H]+ Calcd for C43H75N10O8S2, 923.5;
found; 923.4, HRMS-FAB (m/z): [M+H]+ Calcd for C43H75N10O8S2,
923.5211. Found; 923.5204.
C81H125BF2N10O19, 1613; found 1613.