Synthesis and cytotoxic activity of benzo[a]acronycine and benzo[b]acronycine substituted on the A ring

Article abstract of DOI:10.1016/j.ejmech.2011.02.050

The impact of substitutions at position 10 in the A ring of the cytotoxic benzo[a]acronycine and benzo[b]acronycine series has been explored. 10-Bromobenzo[a] and 10-bromobenzo[b]acronycine were prepared in 12% and 15% yield respectively from commercially

Full text of DOI:10.1016/j.ejmech.2011.02.050

European Journal of Medicinal Chemistry 46 (2011) 1861e1873
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European Journal of Medicinal Chemistry
journal homepage: http://www.elsevier.com/locate/ejmech
Original article
Synthesis and cytotoxic activity of benzo[a]acronycine and benzo[b]acronycine
substituted on the A ring
,
a
a
b
b
Thomas Gaslonde a , Fabiola Covello , Laura Velazquez-Alonso , Stéphane Léonce , Alain Pierré ,
*
Bruno Pfeiffer b, Sylvie Michel a, François Tillequin a
a Laboratoire de Pharmacognosie, Université Paris Descartes, UMR/CNRS 8638, Faculté des Sciences Pharmaceutiques et Biologiques, 4 avenue de l’Observatoire, 75006 Paris, France
b Institut de recherche Servier, Division recherche cancérologie, 125 chemin de ronde, 78290 Croissy sur Seine, France
a r t i c l e i n f o
a b s t r a c t
Article history:
The impact of substitutions at position 10 in the A ring of the cytotoxic benzo[a]acronycine and benzo[b]
acronycine series has been explored. 10-Bromobenzo[a] and 10-bromobenzo[b]acronycine were
prepared in 12% and 15% yield respectively from commercially available chemicals. Their 1,2-dihydro-1,2-
dihydroxy diesters were synthesized. The different derivatives were tested against two cell lines KB-3-1
and L1210. Their cytotoxic activities were found in the same range of magnitude as their non-substituted
counterparts. These structureeactivity relationships permitted to conclude that the introduction of
a substituent at position 10 maintains the activity in both the benzo[a] and [b]acronycine series and open
the way to further pharmacomodulations.
Received 11 January 2011
Received in revised form
16 February 2011
Accepted 18 February 2011
Available online 26 February 2011
Keywords:
Acronycine
Benzo[a]acronycine
Benzo[b]acronycine
Cytotoxicity
Ó 2011 Elsevier Masson SAS. All rights reserved.
1. Introduction
[a], benzo[b] and benzo[c]acronycine (5, 6, and 7, respectively)
series [10e12]. When tested against L1210 cell proliferation, both
Acronycine (1), a natural pyranoacridone first isolated from
Acronycia baueri Schott (Rutaceae) [1] was shown to exhibit anti-
tumor properties against a large panel of tumor cell lines [2,3]
(Chart 1). Nevertheless, its moderate potency and its low solu-
bility in aqueous solvents hampered subsequent clinical trials,
which only gave poor results [4]. Consequently, several efforts were
performed toward the design of more potent derivatives in acro-
nycine series. Substitution of the aromatic A ring at position 11 gave
rise to bioactive compounds. Indeed, 11-methoxyacronycine (2),
10,11-dimethoxyacronycine (3) and 11-aminoacronycine (4) were
found to inhibit the proliferation of human HL60 promyelocytic
leukemic cell line or murine leukemic L1210 cell line, indicating
that substitution on A ring is not detrimental to the activity [5e7].
The first significant improvements in terms of potency were
obtained with compounds substituted on the 1,2 double bond of
the pyran ring, such as diesters of cis- and trans-1,2-dihydroxy-1,2-
dihydroacronycine that exhibited marked antitumor properties
when compared with acronycine [8,9]. Subsequently, structural
analogs including an additional aromatic ring fused onto the
acronycine skeleton were developed, in the three isomeric benzo
benzo[a]acronycine (5) and benzo[b]acronycine (6) were found
some 5-fold more cytotoxic than acronycine (1). On the opposite,
benzo[c]acronycine (7) displayed a cytotoxicity within the same
order of magnitude as acronycine [13]. cis-1,2-Diesters in the first
two series displayed a better antitumor activity in vivo at a 32-fold
smaller dose than acronycine itself [10,11]. The most interesting of
them, (ꢀ)-cis-1,2-diacetoxy-1,2-dihydrobenzo[b]acronycine (8)
was selected for phase I clinical trials under the code S23906-1 [14].
Its mechanism of action implies elimination of the acetoxy group at
position 1 to generate a carbocation that is responsible for the
alkylation of NH2 groups of DNA guanine units in the minor groove
[15,16]. The covalent binding to DNA of S23906-1 (8) was shown
to induce a marked destabilization of the double helix, with the
formation of single-stranded DNA [15,17,18], resulting in an inc-
rease of the cyclin E level in cells which were arrested in the
S-phase and subsequently underwent apoptosis [18,19].
In this context, the positive role played by the substitution on A
ring of acronycine stimulated us to explore the impact of substi-
tutions in the A ring of the most cytotoxic benzo[a]acronycine and
benzo[b]acronycine series. In order to avoid a steric hindrance at
carbon 1, unfavorable to biological activity, as shown by the weak
activity of benzo[c]acronycine, position 10 was chosen to insert
the substituent. We report herein the synthesis and the biologi-
cal evaluation of 10-bromobenzo[a] and benzo[b]acronycine. The
* Corresponding author. Tel.: þ33 1 53 73 98 05; fax: þ33 1 40 46 96 58.
E-mail address: thomas.gaslonde@parisdescartes.fr (T. Gaslonde).
0223-5234/$ e see front matter Ó 2011 Elsevier Masson SAS. All rights reserved.
doi:10.1016/j.ejmech.2011.02.050

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T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
Chart 1. Structures of acronycine derivatives (1e4), benzo[a]acronycine (5), benzo[b]acronycine (6), benzo[c]acronycine (7) and (ꢀ)-cis-1,2-diacetoxy-1,2-dihydrobenzo[b]acro-
nycine (S23906-1) (8).
corresponding 1,2-dihydro-1,2-dihydroxy diesters were also pre-
pared in both series, in order to compare their activity with their
non-substituted counterparts.
position 3 by 3-chloro-3-methylbut-1-yne was successfully per-
formed in the presence of potassium carbonate and potassium
iodide [23], to give the expected inseparable mixture of propargylic
ether 21 and 10-bromo-6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-
benzo[a]pyrano[3,2-h]acridin-7-one (22), in a 70/30 ratio (NMR) in
40% overall yield, accompanied by smaller amounts of the rear-
ranged C-alkylation products 3-bromo-12-hydroxy-9,9-dimethyl-8-
methylidene-10-(1,1-dimethylpropyn-1-oxy)-8,9-dihydro-13H-
benzo[a]pyrrolo[1,2,3-fg]acridin-13-one (23) and 3-bromo-10,12-
dihydroxy-9,9-dimethyl-8-methylidene-8,9-dihydro-13H-benzo[a]
pyrrolo[1,2,3-fg]acridin-13-one (24), isolated in 4% and 1% yield,
respectively [6]. The crude mixture of 21 and 22 was heated at 130 ꢁC
in DMF for 3 h, in order to achieve the thermal rearrangement of the
propargylic ether. N- and O-Methylation reactions of acridone 22 by
methyl iodide in DMF were performed in a one pot process involving
successive additions of a weak (sodium carbonate) and a strong
(sodium hydride) base in the reaction medium, affording the desired
bromobenzo[a]acronycine (9) in 90% yield.
2. Results and discussion
2.1. Chemistry
2.1.1. Synthesis of 10-bromobenzo[a]acronycine (9)
Synthesis of 10-bromo-6-methoxy-3,3,14-trimethyl-3,14-dihy-
dro-7H-benzo[a]pyrano[3,2-h]acridin-7-one (9) was envisioned
through the cyclization in alkaline medium of an intermediate
diarylketone, prepared by FriedeleCrafts acylation of an aniline
precursor with a suitable naphthalenecarboxylic acid [9,20,21]
(Scheme 1 and Chart 2).
Optimization of the conditions described by Nguyên-Hóan [22]
for the formylation of the commercially available 2-bromo-6-
methoxynaphthalene (10) by N-methylformanilide and phosphorus
oxychloride, gave 6-bromo-2-methoxy-1-naphthaldehyde (11) in
a better 88% yield. Oxidation to carboxylic acid 12 was performed by
reaction with potassium permanganate in acetone. Subsequent
treatment with thionyl chloride afforded the corresponding acyl
chloride 13. FriedeleCrafts acylation of 3,5-dimethoxyacetanilide
(14) with 6-bromo-2-methoxy-1-naphthoyl chloride (13) using
stannic chloride as catalyst gave the desired diarylketone 15,
accompanied by smaller amounts of compound 16 (Chart 2),
resulting from a trans-amidification reaction of diarylketone 15, and
2-bromo-6-methoxynaphthalen (10) formed by decarboxylation of
13. It should be noted that the choice of the Lewis acid catalyst had
a dramatic influence on the course of the reaction. For instance, the
use of aluminium chloride gave a mixture of the desired diary-
lketone 15 and its regioisomer 17 (51% and 14% respectively).
Cyclization of diarylketone 15 to the corresponding benzoacridone
was achieved by the use of sodium hydride in dimethylforma-
mide. Thus, 3-bromo-9,11-dimethoxybenzo[a]acridin-12(7H)-one
(18) was obtained in 77% yield, accompanied by smaller amounts of
diarylethylene 19 isolated in 14% yield. The acridone 18 was depro-
tected upon treatment with boron tribromide in dichloromethane
to give 3-bromo-9,11-dihydroxybenzo[a]acridin-12(7H)-one (20) in
quantitative yield. Regioselective O-alkylation of compound 20 at
2.1.2. Synthesis of 10-bromobenzo[b]acronycine (25)
The same successful synthetic strategy used for the preparation of
the angular 10-bromobenzo[a]acronycine (9) was followed for the
synthesis of 10-bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-
7H-benzo[b]pyrano[3,2-h]acridin-7-one (25) (Scheme 2 and Chart 3).
Accordingly, the acyl chloride 26 was first obtained from the
commercially available 3-hydroxy-2-naphthoic acid in four steps,
following the procedure of Murphy et al. [24]. FriedeleCrafts
reaction of 3,5-dimethoxyacetanilide (14) with compound 26 aff-
orded the desired diarylketone 27 in a good 81% yield, accompanied
by 9% of the trans-amidified diarylketone 28. Surprisingly, in
alkaline medium, the diarylketone 27 did not cyclize to the acri-
done 29, but gave the 4-aryl-2-quinolinone 30 in 50% yield,
accompanied by the deprotected diarylketone 31 isolated in 10%
yield. Compound 30 can be considered as arising from an intra-
molecular aldol condensation involving the acetyl group [20,21].
Therefore, the diarylketone 27 was first deprotected by acid
hydrolysis of the amide group and the resulting aminodiarylketone
31 cyclized, upon treatment with sodium hydride, to the acridone
29 in a good 74% overall yield from 27. It should be noted that,
under similar alkaline conditions, compound 28, without hydrogen

T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
1863
Scheme 1. Synthesis of 10-bromobenzo[a]acronycine (9).
atom at
a
-position of the carbonyl amide group, also gave the
(35) isolated in 4% yield. After heating in dimethylformamide at
130 ꢁC for 3.5 h, the mixture of 33 and 34 gave pure 10-bromo-6-
hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]
acridin-7-one (34) in 38% overall yield from 32. Finally, methylation
at N-14 and O-6 was achieved using the similar one pot method
previously used for the preparation of 9 from 22. Under these
conditions, the desired linear bromobenzo[b]acronycine 25 was
obtained in 82% yield, together with small amount of its phenolic
counterpart 36, isolated in 12% yield.
acridone 29, although in a smaller 30% yield. Conversion of the
dimethoxyacridone 29 to the corresponding dihydroxyacridone 32
could only be successfully conducted when a solution of hydrogen
bromide in acetic acid was used as deprotecting agent. Treatment of
32 with 3-chloro-3-methylbut-1-yne gave as previously an insep-
arable mixture of the desired propargylic ether 33 and cyclized
compound 34, accompanied by 9-bromo-5-hydroxy-1,1-dimethyl-
2-methyliden-1,2-dihydrobenzo[b]furo[3,2-h]acridin-6(13H)-one
Chart 2. Structures of secondary products 16, 17, 19, 23 and 24 obtained from synthesis described in Scheme 1.

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T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
Scheme 2. Synthesis of 10-bromobenzo[b]acronycine (25).
2.1.3. Synthesis of 1,2-diesters in 10-bromobenzo[a]acronycine and
10-bromobenzo[b]acronycine series
series exhibited similar biological profiles. Indeed, diacetates and
cyclic carbonates 39e42 displayed submicromolar ICs50, in the
The (ꢀ)-cis-diols 37 and 38 were conveniently obtained in 64%
and 97% yield, respectively, by catalytic osmium tetroxide oxidation
of 9 and 25, using N-methylmorpholine N-oxide to regenerate the
oxidative agent [8] (Schemes 3 and 4 ). Acetylation of the diols 37
and 38 was ensured by use of excess acetic anhydride to give the
corresponding diacetates 39 and 40 in 93 and 98% yield, respec-
tively. Finally, treatment of the angular and the linear diols 37 and
38 with N,N0-carbonyldiimidazole in 2-butanone afforded the cyclic
carbonates 41 and 42.
range of 0.011e0.6 mM, and were found more active against KB-3-1
solid tumor cell line than leukemic L1210 cell line. Also, compounds
9 and 25 with the 1,2 double bond and the corresponding diols 37
and 38 were less active. These results are in full agreement with
the mechanism of action previously established for S-23096-1 in
the benzo[b]acronycine series. When compared to their previou-
sly reported unsubstituted analogs, the cytotoxic activity of the
10-bromo compounds lie within the same range of potency,
excepted for compound 9, which is ca. 5-fold more potent against
both cell lines than its unsubstituted counterpart 5 (Chart 4).
2.2. Pharmacology
3. Conclusion
The biological profile of the newly synthesized molecules in
both benzo[a] and benzo[b]acronycine series was determined by
their capacity to inhibit proliferation of murine leukemia cell line
(L1210) and human epidermoid carcinoma cell line (KB-3-1). The
results are reported in Tables 1 and 2 . As a general rule, compounds
belonging to both bromobenzo[a] and bromobenzo[b]acronycine
Novel benzoacronycine analogs have been synthesized in the
10-bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo[a]
pyrano[3,2-h]acridin-7-one and 10-bromo-6-methoxy-3,3,14-tri-
methyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]acridin-7-one series.
The different derivatives were tested against two cell lines KB-3-1 and

T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
1865
Chart 3. Structures of secondary products 28, 30, 35 and 36 obtained from synthesis described in Scheme 2.
L1210. Their cytotoxic potencies were found within the same range of
magnitude as their unsubstituted counterparts. Especially, the activity
of (ꢀ)-cis-1,2-diacetoxy-1,2-dihydrobenzo[b]acronycine 40 is similar
to that of compound 8 that recently underwent phase I clinical trials.
These results permit to conclude that the introduction of a substituent
at position 10 in the A aromatic ring is not detrimental to the activity
in both the benzo[a] and [b]acronycine series and open the way to
further pharmacomodulations.
acetate (250 g) in water (820 mL). After evaporation of the solvents
under reduce pressure the residue is solubilized in ethyl acetate
(1 L) and water (1 L), and extracted with ethyl acetate (6 ꢃ 1 L). The
combined organic layers were washed with water (500 mL), dried
over MgSO4, filtered and evaporated under reduced pressure to
give dark oil which crystallized upon cooling. The filtered solid
was recrystallized in dichloromethane/cyclohexane to give 23.5 g
of 6-bromo-2-methoxy-1-naphthaldehyde (11). Additionally, the
combined filtrates were evaporated under reduce pressure and
furnished after column chromatography on silica gel (C6H12/AcOEt:
9/1: V/V) 27 g more of desired solid 11. Compound 11 was obtained
as white needles (88%), m.p. 103e104 ꢁC (CH2Cl2/C6H12). 1H NMR
4. Experimental section
4.1. Chemistry
(CDCl3)
d
: 4.07 (s, 3H, OMe); 7.34 (d, 1H, J ¼ 9 Hz, H-3), 7.67 (dd, 1H,
The melting points were determined on a Leica VM apparatus
and are not corrected. IR spectra (nmax in cmꢂ1) were obtained from
potassium bromide pellets on a Nicolet-510 FT-IR instrument. UV
spectra were recorded in spectroscopic grade MeOH on a Jenway
J ¼ 9 and 2 Hz, H-7), 7.94 (d, 1H, J ¼ 2 Hz, H-5), 7.98 (d, 1H, J ¼ 9 Hz,
H-4), 9.19 (d, 1H, J ¼ 9 Hz, H-8), 10.87 (s, 1H, CHO). 13C NMR (CDCl3)
d: 56.6 (OMe), 89.7 (C-1), 113.7 (C-3), 116.7 (C-4a), 118.5 (C-6), 126.9
(C-8), 129.8 (C-8a), 130.0 (C-8), 132.9 (C-7), 136.3 (C-4), 163.9 (C-2),
191.6 (CHO). IR (KBr) cmꢂ1: 3099, 2986, 2947, 2881, 2842, 2804,
1666, 1584, 1498, 1456, 1394, 1343, 1266, 1250, 1172, 1153, 1075,
6705 spectrometer. 1H NMR ( [ppm], J [Hz]) and 13C NMR spectra
d
were recorded at 400 and 75 MHz, using Bruker Avance 400 and
Bruker Avance 300 spectrometers, respectively. When necessary,
the signals were unambiguously assigned by 2D NMR techniques:
1He1H COSY, 1He1H NOESY, 13Ce1H HMQC, and 13Ce1H HMBC.
These experiments were performed using standard Bruker micro-
programs. Mass spectra were recorded with a ZQ 2000 Waters
spectrometer using electron spray ionization (MS (ESIþ or ESIꢂ)).
Flash column chromatographies were conducted using silica gel 60
1048, 881, 820, 807. UV lmax (MeOH) nm (log e): 226 (4.56), 247
(4.54), 313 (3.83), 362 (3.71). MS (ESIþ) m/z: 265 and 267
[M þ Na]þ.
4.1.2. 6-Bromo-2-methoxy-1-naphthaoic acid (12)
A
solution of 6-bromo-2-methoxy-1-naphthaldehyde (11)
(20.0 g, 75 mmol) in anhydrous acetone (400 mL) was heated at
70 ꢁC. After addition of a solution of potassium permanganate
(32 g) in water (1 L) for 2 h, the reaction was stirred and heated
further 2 h. An aqueous solution of potassium hydroxide was added
to the reaction mixture to obtain pH ¼ 10. After filtration, the
solution was washed with ethyl acetate (200 mL) and acidified with
hydrochloric acid (10%) to pH ¼ 2. The precipitate was filtered,
washed with water (3 ꢃ 100 mL) and dried in a vacuum over P2O5 to
SDS (20e45
Thin layer chromatographies were performed using Merck TLC
Silica gel 60 F254
mm or 35e70 mm) with an overpressure of 300 mbar.
.
4.1.1. 6-Bromo-2-methoxy-1-naphthaldehyde (11)
N-Methylformanilide (160 mL, 1.3 mol) and phosphorus oxy-
chloride (185 mL, 2.0 mol) were added to a solution of 2-bromo-6-
methoxynaphthalen (10) (51.4 g, 0.22 mol) in anhydrous toluene
(260 mL). The solution was heated at 100 ꢁC for 5 h. The cooled
reaction mixture was cautiously added to a solution of sodium
give 6-bromo-2-methoxy-1-naphthaoic acid (12) as
amorphous solid (14.53 g, 69%). 1H NMR (CDCl3)
: 4.12 (s, 3H,
OMe), 7.37 (d, 1H, J ¼ 9 Hz, H-3), 7.65 (dd, 1H, J ¼ 9 and 2 Hz, H-7),
a white
d

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T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
Scheme 3. Synthesis of 1,2-diesters in 10-bromobenzo[a]acronycine series.
7.92 (d, 1H, J ¼ 9 Hz, H4), 7.98 (d, 1H, J ¼ 2 Hz, H-5), 8.53 (d, 1H,
of the crude 6-bromo-2-methoxy-1-naphthaoyl chloride (13) in
anhydrous dichloroethane (10 mL). The reaction mixture was heated
to 45 ꢁC for 30 min. Then, a solution of 3,5-dimethoxyacetanilide (14)
(0.96 g, 4.92 mmol) in anhydrous dichloroethane (25 mL) was added,
and the mixture was heated at 45 ꢁC for 20 h. The reaction mixture
was added to cold water (300 mL) and extracted with dichloro-
methane (3 ꢃ 150 mL). The combined organic layers were washed
with an aqueous solution of potassium hydroxide (10%) to remove
excess of 6-bromo-2-methoxy-1-naphthaoic acid (12), dried over
MgSO4 and evaporated under reduced pressure. Column chroma-
tography on silica gel (CH2Cl2/MeOH: 100/0 to 95/5: V/V) gave
successively 2-bromo-6-methoxynaphthalene (210 mg), (6-bromo-
2-methoxynapht-1-yl)-[2-(6-bromo-2-methoxy-1-naphthamido)-
4,6-dimethoxyphenyl]ketone (16) (47 mg,1%) as a white amorphous
J ¼ 9 Hz, H-8). 13C NMR (CDCl3)
d: 57.3 (OMe), 113.9 (C-3), 114.6
(C-1), 118.5 (C-6), 126.8 (C-8), 130.1 (C-5 and C-4a), 130.4 (C-8a),
131.6 (C-7), 132.8 (C-4), 156.2 (C-2), 168.8 (COOH). IR (KBr) cmꢂ1
2982, 2943, 2889, 1700, 1669, 1588, 1499, 1433, 1343, 1293, 1254,
1149, 1083, 1017, 916, 873, 818. UV lmax (MeOH) nm (log ): 235
:
e
(4.82), 272 (3.70), 282 (3.78), 293 (3.65), 331 (3.39), 343 (3.42). MS
(ESIꢂ) m/z: 279 and 281 [M ꢂ H]ꢂ.
4.1.3. (6-Bromo-2-methoxynapht-1-yl)-(2-acetamido-4,6-
dimethoxyphenyl)ketone (15) and (6-bromo-2-methoxynapht-1-yl)-
[2-(6-bromo-2-methoxy-1-naphthamido)-4,6-dimethoxyphenyl]
ketone (16)
Thionyl chloride (12.0 mL) was added to 6-bromo-2-methoxy-1-
naphthaoic acid (12) (2.10 g, 7.47 mmol). The reaction mixture was
stirred at 65 ꢁC for 3 h and evaporated under reduced pressure to
give crude 6-bromo-2-methoxy-1-naphthaoyl chloride (13) which
was immediately used in the following step without further purifi-
cation. Stannic chloride (1.0 mL, 8.86 mmol) was added to a solution
solid,
(6-bromo-2-methoxynapht-1-yl)-(2-acetamido-4,6-dime-
thoxyphenyl)ketone (15) (1.67 g, 72%) as a yellowish amorphous
solid and 3,5-dimethoxyacetanilide (14) (124 mg). (6-Bromo-2-
methoxynapht-1-yl)-[2-(6-bromo-2-methoxy-1-naphthamido)-4,6-
dimethoxyphenyl]ketone (16).1H NMR (CDCl3) : 3.09 (s, 3H, OMe-60),
d

T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
1867
Scheme 4. Synthesis of 1,2-diesters in 10-bromobenzo[b]acronycine series.
3.81 (s, 3H, OMe-2), 3.95 (s, 3H, OMe-200), 3.99 (s, 3H, OMe-40), 6.07
898. UV lmax (MeOH) nm (log
e
): 235 (5.08), 283 (4.21), 294 (4.22).
(d, 1H, J ¼ 2 Hz, H-50), 7.27 (d, 1H, J ¼ 9 Hz, H-3), 7.32 (d, 1H, J ¼ 9 Hz,
H-300), 7.41 (dd, H, J ¼ 9 and 1.5 Hz, H-7), 7.43 (d, 1H, J ¼ 9 Hz, H-8),
7.55 (dd, 1H, J ¼ 9 and 2 Hz, H-700), 7.72 (d, 1H, J ¼ 9 Hz, H-4), 7.80
(d,1H, J ¼ 9 Hz, H-400), 7.93 (d,1H, J ¼ 1.5 Hz, H-5), 7.95 (d,1H, J ¼ 2 Hz,
H-500), 7.99 (d, 1H, J ¼ 9 Hz, H-800), 8.46 (d, 1H, J ¼ 2 Hz, H-60), 12.42
MS (ESIþ) m/z: 700, 702 and 704 [M þ Na]þ. (6-Bromo-2-me-
thoxynapht-1-yl)-(2-acetamido-4,6-dimethoxyphenyl)ketone (15). 1H
NMR (CDCl3) d
: 2.29 (s, 3H, COMe), 3.05 (s, 3H, OMe-60), 3.82 (s, 3H,
OMe-2), 3.89 (s, 3H, OMe-40), 5.98 (d,1H, J ¼ 2.5 Hz, H-50), 7.29 (d,1H,
J ¼ 9 Hz, H-3), 7.42 (m, 2H, H-7 and H-8), 7.74 (d, 1H, J ¼ 9 Hz, H-4),
7.94 (s, 1H, H-5), 8.15 (d, 1H, J ¼ 2.5 Hz, H-30), 12.24 (s, 1H, NH). 13C
(s, 1H, NH). 13C NMR (CDCl3) : 55.7 (OMe-60), 55.9 (OMe-40), 56.6
d
(OMe-200), 57.0 (OMe-2), 94.9 (C-50), 97.5 (C-30), 110.2 (C-20), 114.2
(C-300),114.6 (C-3),117.5 (C-6),117.9 (C-600),121.0 (C-4a00),125.6 (C-8),
126.2 (C-800),128.9 (C-4a),129.0 (C-4),129.3 (C-8a),129.9 (C-1),130.0
(C-100 and C-8a00), 130.07 (C-5), 130.14 (C-500), 130.2 (C-7), 130.9 (C-4
and C-700), 144.1 (C-10), 152.9 (C-2), 154.3 (C-200), 163.1 (C-60), 165.9
(C-40), 166.6 (CONH), 197.3 (ArCOAr0). IR (KBr) cmꢂ1: 3350, 3124,
3062, 3003, 2937,1606,1587,1520,1497,1446,1271,1252,1143,1077,
NMR (CDCl3) d
: 25.9 (COMe), 55.7 (OMe-40, OMe-60), 57.0 (OMe-2),
94.4 (C-50), 97.0 (C-30), 109.6 (C-10), 114.6 (C-3), 117.5 (C-6), 125.8
(C-8), 128.8 (C-4), 129.2 (C-8a), 129.4 (C-4a), 130.0 (C-1, C-5), 130.2
(C-7), 144.7 (C-20), 152.8 (C-2), 163.3 (C-60), 166.0 (C-40), 170.1
(CONH), 197.5 (ArCOAr). IR (KBr) cmꢂ1: 3203, 3126, 3004, 2959,
2935, 2834, 1697, 1611, 1584, 1518, 1497, 1444, 1273, 1247, 1199, 1160,
Table 2
Table 1
Cytotoxicity of bromo compounds 36, 25, 38, 40, 42 in comparison with
non-substituted compounds 6, 8, 45 in benzo[b]acronycine series.
Cytotoxicity of bromo compounds 22, 23, 24, 9, 37, 39, 41 in comparison with non-
substituted compounds 5, 44, 43 in benzo[a]acronycine series.
Compounds
36
0.645 2.2 14.9
14.3 9.9 3.4 36.3
25
6
38
40
8
42
45
Compounds
22 23
3.4 51.1 7.3 0.49 2.5 7.6 0.4
1.7 37.1 2.5 1.3 8.6 5.5 0.040 0.14 0.015 0.015
24
9
5
37 39
44
41
43
IC50 L1210,
m
M
0.225 0.6
0.79
0.034 0.016
IC50 L1210,
m
M
0.73 0.08
0.059
IC50 KB-3-1,
m
M
0.115 0.095 0.011 n.t.
IC50 KB-3-1,
mM
n.t.: not tested.

1868
T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
Chart 4. Reference 1,2-diesters in the benzo[a] and benzo[b]acronycine series.
1144, 1109, 1086, 904, 803. UV lmax (MeOH) nm (log
e
): 236 (4.91),
temperature for 2 h and poured on cold water (3 L). The precipitate
was filtered and dried in a vacuum over P2O5. The solid was washed
with dichloromethane (3 ꢃ 70 mL) and filtered to give 3-bromo-
9,11-dimethoxybenzo[a]acridin-12(7H)-one (18) (9.72 g, 77%) as an
amorphous white solid. Then, the combined organic layers were
dried over MgSO4, filtered and evaporated under reduced pressure.
Column chromatography on silica gel (CH2Cl2/MeOH: 100/0 to
95/5: V/V) gave 1-(6-bromo-2-methoxynapht-1-yl)-1-(2-acet-
amido-4,6-dimethoxyphenyl)ethylene (19) (2.09 g, 14%) as white
prisms, m.p. 175e176 ꢁC (CH2Cl2). 3-Bromo-9,11-dimethoxybenzo[a]
307 (4.24). MS (ESIþ) m/z: 480 and 482 [M þ Na]þ, 496 and 498
[M þ K]þ.
4.1.4. (6-Bromo-2-methoxynapht-1-yl)-(2-acetamido-4,
6-dimethoxyphenyl)ketone (15) and (6-bromo-2-methoxynapht-1-
yl)-(4-acetamido-2,6-dimethoxyphenyl)ketone (17)
Thionyl chloride (6.0 mL) was added to 6-bromo-2-methoxy-1-
naphthaoic acid (12) (1.00 g, 3.56 mmol). The reaction mixture was
stirred at 65 ꢁC for 3 h and evaporated under reduced pressure to give
crude 6-bromo-2-methoxy-1-naphthaoyl chloride (13) which was
immediately used in the following step without further purification.
Aluminium trichloride (0.87 g, 6.52 mmol) was added to a solution of
the crude 6-bromo-2-methoxy-1-naphthaoyl chloride (13) in
anhydrous dichloroethane (3 mL). The reaction mixture was heated
to ꢂ30 ꢁC for 30 min. Then, a solution of 3,5-dimethoxyacetanilide
(14) (0.56 g, 2.87 mmol) in anhydrous dichloroethane (6 mL) was
added, and the mixture was heated at ꢂ30 ꢁC for 6 days. A cold
solution of hydrochloric acid (400 mL,15%) was added to the reaction
mixture. After extraction with dichloromethane (3 ꢃ 50 mL), the
combined organic layers were washed with an aqueous solution of
potassium hydroxide (10%) to remove excess of 6-bromo-2-
methoxy-1-naphthaoic acid (12), dried over MgSO4 and evaporated
under reduced pressure. Column chromatography on silica gel
(CH2Cl2/MeOH: 100/0 to 95/5: V/V) gave successively (6-bromo-2-
methoxynapht-1-yl)-(2-acetamido-4,6-dimethoxyphenyl)ketone
(15) (670 mg, 51%) as a yellowish amorphous solid and (6-bromo-2-
methoxynapht-1-yl)-(4-acetamido-2,6-dimethoxyphenyl)ketone
(17) (180 mg, 14%) as a white amorphous solid. (6-Bromo-2-
methoxynapht-1-yl)-(4-acetamido-2,6-dimethoxyphenyl)ketone (17).
acridin-12(7H)-one (18). 1H NMR (CDCl3 þ CD3OD)
d: 3.69 (s, 3H,
OMe-11), 3.97 (s, 3H, OMe-9), 6.11 (m, 2H, H-8 and H-10), 7.14
(d, 1H, J ¼ 9 Hz, H-6), 7.62 (d, 1H, J ¼ 9 Hz, H-5), 7.71 (dd, 1H, J ¼ 9
and 1.5 Hz, H-2), 7.84 (d, 1H, J ¼ 1.5 Hz, H-4), 10.14 (d, 1H, J ¼ 9 Hz,
H-1). 13C NMR (CDCl3 þ CD3OD)
d: 55.0 (OMe-11), 55.7 (OMe-9),
89.8 (C-10), 93.8 (C-8), 109.3 (C-11a),114.0 (C-12a),118.1 (C-6), 118.2
(C-3), 128.5 (C-1), 130.0 (C-4), 130.4 (C-4a), 130.7 (C-12b), 131.2
(C-2), 133.1 (C-5), 140.5 (C-7a), 142.6 (C-6a), 161.7 (C-9), 163.0
(C-11), 179.2 (C-12). IR (KBr) cmꢂ1: 3435, 3290, 3185, 3132, 3097,
3029, 2962, 1637, 1606, 1581, 1534, 1452, 1398, 1206, 1162, 1129,
1077, 831. UV lmax (MeOH) nm (log e): 203 (4.48), 218 (4.33), 245
(4.40), 253 (4.37), 291 (4.81), 319 (4.00), 357 (3.48), 373 (3.66), 392
(3.65). MS (ESIþ) m/z: 384 and 386 [M þ H]þ, 406 and 408
[M þ Na]þ. 1-(6-Bromo-2-methoxynapht-1-yl)-1-(2-acetamido-4,6-
dimethoxyphenyl)ethylene (19). 1H NMR (CDCl3)
d: 2.17 (s, 3H,
COMe), 3.32 (s, 3H, OMe-60), 3.74 (s, 3H, OMe-2), 3.83 (s, 3H, OMe-
40), 5.61 (d, 1H, J ¼ 2 Hz, CH2), 5.72 (d, 1H, J ¼ 2 Hz, CH2), 6.13 (d, 1H,
J ¼ 2 Hz, H-50), 7.20 (d,1H, J ¼ 9 Hz, H-3), 7.53 (dd,1H, J ¼ 9 and 2 Hz,
H-7), 7.61 (d, 1H, J ¼ 2 Hz, H-30), 7.67 (d, 1H, J ¼ 9 Hz, H-4), 7.93
(d, 1H, J ¼ 2 Hz, H-5), 8.30 (d, 1H, J ¼ 9 Hz, H-8), 8.33 (s, 1H, NH). 13C
1H NMR (DMSO-d6)
d
: 2.04 (s, 3H, COMe), 3.47 (s, 6H, OMe60 and
NMR (CDCl3) d
: 24.7 (COMe), 55.0 (OMe-60), 55.4 (OMe-40), 56.6
OMe20), 3.64 (s, 3H, OMe2), 6.95 (s, 2H, H-30 and H-50), 7.45 (d, 1H,
J ¼ 9 Hz, H-3), 7.58 (dd, 1H, J ¼ 9 and 2 Hz, H-7), 7.74 (d, 1H, J ¼ 9Hz,
H-8), 7.98 (d, 1H, J ¼ 9 Hz, H-4), 8.16 (d, 1H, J ¼ 2 Hz, H-5), 10.09
(OMe-2), 94.9 (C-50), 98.1 (C-30), 114.3 (C-3), 114.5 (C-10), 117.5 (C-6),
125.2 (CH2), 126.7 (C-1), 128.0 (C-4), 128.6 (C-8), 128.9 (C-7), 129.5
(C-5), 130.6 (C-4a), 131.8 (C-8a), 137.2 (C-20), 138.3 (C]CH2), 153.3
(C-2), 158.2 (C-60), 159.9 (C-40), 168.3 (CONH). IR (KBr) cmꢂ1: 3404,
3070, 2993, 2962, 2941, 2836, 1689, 1585, 1529, 1529, 1493, 1447,
1427, 1334, 1252, 1143, 1108, 1073, 821, 800. UV lmax (MeOH) nm
(s, 1H, NH). 13C NMR (DMSO-d6) : 24.8 (COMe), 56.2 (OMe20 and
d
OMe60), 57.4 (OMe2), 95.65 (C30 and C50),116.3 (C3),116.6 (C10),117.1
(C6), 126.8 (C4a), 127.2 (C8), 130.1 (C1), 130.2 (C8a), 130.3 (C5), 130.4
(C7), 131.4 (C4), 143.1 (C40), 155.8 (C2), 158.9 (C20 and C60), 169.3
(CONH), 195.0 (ArCOAr). IR (KBr) cmꢂ1: 3308, 3001, 2966, 2935,
2838,1681,1658,1602,1533,1499,1453,1405,1273,1250,1231,1130,
(log e
): 237 (4.85), 286 (4.00), 341 (3.48). MS (ESIþ) m/z: 478 and
480 [M þ Na]þ, 494 and 496 [M þ K]þ.
897. UV lmax (MeOH) nm (log
e
): 233 (4.76), 297 (4.10). MS (ESIþ) m/z:
4.1.6. 3-Bromo-9,11-dihydroxybenzo[a]acridin-12(7H)-one (20)
Boron tribromide (19.7 mL, 208 mmol) was added to a solution of
3-bromo-9,11-dimethoxybenzo[a]acridin-12(7H)-one (18) (10.0 g,
26.0 mmol) in anhydrous dichloromethane (530 mL). The reaction
mixture was stirred at 45 ꢁC for 27 h, and then, added on icy water
(1.2 L). The solid was filtered, washed with water (3 ꢃ 150 mL),
washed with dichloromethane (3 ꢃ 50 mL) and dried in a vacuum
over P2O5 to give 3-bromo-9,11-dihydroxybenzo[a]acridin-12(7H)-
one (20) (9.29 g,100%) as a yellowamorphous solid.1H NMR (DMSO-
480 and 482 [M þ Na]þ, 496 and 498 [M þ K]þ.
4.1.5. 3-Bromo-9,11-dimethoxybenzo[a]acridin-12(7H)-one (18)
and 1-(6-bromo-2-methoxynapht-1-yl)-1-(2-acetamido-4,6-
dimethoxyphenyl)ethylene (19)
A solution of (6-bromo-2-methoxynapht-1-yl)-(2-acetamido-
4,6-dimethoxyphenyl)ketone (15) (15.00 g, 32.8 mmol) in anhy-
drous N,N-dimethylformamide (240 mL) was added to a suspension
of sodium hydride (3.93 g, 98.2 mmol) in anhydrous N,N-dime-
thylformamide (100 mL). The reaction mixture was stirred at room
d6)
d
: 6.09 (d, 1H, J ¼ 1.5 Hz, H-8), 6.39 (d, 1H, J ¼ 1.5 Hz, H-10), 7.61
(d, 1H, J ¼ 9 Hz, H-6), 7.82 (dd, 1H, J ¼ 9 and 1.5 Hz, H-2), 8.15

T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
1869
(d,1H, J ¼ 9 Hz, H-5), 8.25 (d,1H, J ¼ 1.5 Hz, H-4), 9.95 (d,1H, J ¼ 9 Hz,
(C-9a),111.1 (C-13a),118.9 (C-3),120.4 (C-6),128.9 (C-1),129.7 (C-4a),
131.0 (C-4),131.5 (C-13b),132.0 (C-2),135.3 (C-5),136.3 (C-9b),143.1
(C-6a), 161.2 (C-12), 165.1 (C-10), 172.7 (C-8), 183.2 (CO). IR (KBr)
cmꢂ1: 3388, 2952, 2921, 2852, 1647, 1586, 1493, 1457, 1437, 1161,
H-1), 10.51 (s, 1H, OH-9), 10.51 (s, 1H, NH), 14.78 (s, 1H, OH-11). 13C
NMR (DMSO-d6)
d: 91.4 (C-8), 97.5 (C-10), 106.0 (C-11a), 110.6
(C-12a),118.4 (C-3),119.8 (C-6),128.6 (C-1),130.3 (C-4a),131.0 (C-4),
131.1 (C-12b), 131.8 (C-2), 135.0 (C-5), 142.0 (C-7a), 142.7 (C-6a),
164.0 and 164.1 (C-9 and C-11), 182.3 (C-12). IR (KBr) cmꢂ1: 3358,
3132, 3055, 3013, 1647, 1586, 1499, 1411, 1180, 1165, 1134, 826. UV
1139, 1088, 829, 796. UV lmax (MeOH) nm (log e): 203 (4.59), 224
(4.38), 246 (4.29), 257 (4.32), 296 (4.67), 392 (3.50). MS (ESIþ) m/z:
422 and 424 [M þ H]þ, 444 and 446 [M þ Na]þ.10-Bromo-6-hydroxy-
3,3-dimethyl-3,14-dihydro-7H-benzo[a]pyrano[3,2-h]acridin-7-one
lmax (MeOH) nm (log e): 202 (4.42), 223 (4.32), 238 (4.25), 256
(4.35), 294 (4.71), 325 (3.92), 389 (3.50). MS (ESIþ) m/z: 354 and 356
[M þ H]þ.
(22).1H NMR (DMSO-d6)
d
: 1.45 (s, 6H, C-3Me2), 5.75 (d,1H, J ¼ 10 Hz,
H-2), 6.14 (s, 1H, H-5), 7.18 (d, 1H, J ¼ 10 Hz, H-1), 7.83 (dd, 1H, J ¼ 9
and 2 Hz, H-9), 7.98 (d,1H, J ¼ 9 Hz, H-13), 8.19 (d,1H, J ¼ 9 Hz, H-12),
8.25 (d,1H, J ¼ 2 Hz, H-11), 7.94 (d,1H, J ¼ 9 Hz, H-8),11.49 (s,1H, NH),
4.1.7. 10-Bromo-6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo
[a]pyrano[3,2-h]acridin-7-one (22), 3-bromo-12-hydroxy-9,9-
dimethyl-8-methylidene-10-(1,1-dimethylpropyn-1-oxy)-8,9-
dihydro-13H-benzo[a]pyrrolo[1,2,3-fg]acridin-13-one (23) and
3-bromo-10,12-dihydroxy-9,9-dimethyl-8-methylidene-8,9-
15.16 (s, 1H, OH). 13C NMR (DMSO-d6)
d: 28.1 (C-3Me2), 77.7 (C-3),
98.0 (C-5), 98.8 (C-14b), 106.7 (C-6a), 111.0 (C-7a), 116.6 (C-1), 118.7
(C-10), 120.1 (C-13), 126.5 (C-2), 128.7 (C-8), 129.9 (C-11a), 131.0
(C-11), 131.4 (C-7b), 132.0 (C-9), 135.2 (C-12), 136.5 (C-14a), 143.1
(C-13a), 159.0 (C-4a), 164.2 (C-6), 182.7 (CO). IR (KBr) cmꢂ1: 3379,
2967, 2921, 1642, 1583, 1546, 1488, 1375, 1174, 1145, 1124, 893, 833,
dihydro-13H-benzo[a]pyrrolo[1,2,3-fg]acridin-13-one (24)
Anhydrous potassium carbonate (8.82 g, 42.1 mmol), anhydrous
potassium iodide (7.00 g, 42.1 mmol) and 3-chloro-3-methylbut-1-
yne (7.75 mL, 72.1 mmol) were added to a solution of 3-bromo-9,11-
dihydroxybenzo[a]acridin-12(7H)-one (20) (5.00 g, 14.0 mmol) in
anhydrous N,N-dimethylformamide (200 mL). The reaction mixture
was stirred at 65 ꢁC for 27 h, poured in water (2.5 L) and then,
extracted with dichloromethane/methanol: 10/1: V/V (9 ꢃ 1 L). The
combined organic layers were dried over MgSO4, filtered and
evaporated under reduced pressure. Column chromatography on
silica gel (CH2Cl2/C6H12: 50/50 to 100/0: V/V) gave successively
3-bromo-12-hydroxy-9,9-dimethyl-8-methylidene-10-(1,1-dime-
thylpropyn-1-oxy)-8,9-dihydro-13H-benzo[a]pyrrolo[1,2,3-fg]acri-
din-13-one (23) (290 mg, 4%) as a orange-yellow amorphous solid,
3-bromo-10,12-dihydroxy-9,9-dimethyl-8-methylidene-8,9-dihy-
dro-13H-benzo[a]pyrrolo[1,2,3-fg]acridin-13-one (24) (44.5 mg,1%)
as a orange-yellow amorphous solid, and a mixture of 3-bromo-11-
hydroxy-9-(1,1-dimethylpropyn-1-oxy)-benzo[a]acridin-12(7H)-
one (21) and 10-bromo-6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-
benzo[a]pyrano[3,2-h]acridin-7-one (22) (3.37 g). The mixture of
compound 21 and 22 was dissolved in anhydrous N,N-dime-
thylformamide (200 mL). The solutionwas heated to 130 ꢁC for 3.5 h,
and poured on cold water (1 L). The solid was filtered, washed with
water (3 ꢃ 50 mL) and driedin avacuumover P2O5 to give10-bromo-
6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo[a]pyrano[3,2-h]
acridin-7-one (22) (5.53 g, 40%) as a yellow amorphous solid.
3-Bromo-12-hydroxy-9,9-dimethyl-8-methylidene-10-(1,1-dimethyl-
propyn-1-oxy)-8,9-dihydro-13H-benzo[a]pyrrolo[1,2,3-fg]acridin-
759. UV lmax (MeOH) nm (log e): 206 (4.67), 256 (4.38), 265 (4.42),
302 (4.87), 334 (4.05), 406 (3.60). MS (ESIþ) m/z: 422 and 424
[M þ H]þ, 444 and 446 [M þ Na]þ.
4.1.8. 10-Bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-
benzo[a]pyrano[3,2-h]acridin-7-one (9)
Anhydrous sodium carbonate (8.97 g, 84.6 mmol) and methyl
iodide (10.5 mL, 170 mmol) were added to a solution of 10-bromo-
6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo[a]pyrano[3,2-h]
acridin-7-one (22) (7.14 g, 19.9 mmol) in anhydrous N,N-dime-
thylformamide (350 mL). The reaction mixture was heated to 45 ꢁC
for 24 h. Then, a suspension of sodium hydride (170 mmol) in
anhydrous N,N-dimethylformamide (175 mL) and methyl iodide
(5.3 mL, 85 mmol) were added, and the reaction mixture was
heated at 40 ꢁC for more 3 h. After addition of icy water (1 L), the
solid was filtered, washed with water (3 ꢃ 200 mL) and dry in
vacuum over P2O5. Column chromatography on silica gel (CH2Cl2/
MeOH: 100/0 to 99.4/0.6: V/V) gave 10-bromo-6-methoxy-3,3,14-
trimethyl-3,14-dihydro-7H-benzo[a]pyrano[3,2-h]acridin-7-one
(9) as an amorphous yellow solid (6.75 g, 90%). 1H NMR (CDCl3)
d: 1.53 (s, 6H, C-3Me2), 3.78 (s, 3H, NMe), 4.01 (s, 3H, OMe), 5.49
(d, 1H, J ¼ 10 Hz, H-2), 6.37 (s, 1H, H-5), 6.49 (d, 1H, J ¼ 10 Hz, H-1),
7.37 (d, 1H, J ¼ 9 Hz, H-13), 7.67 (dd, 1H, J ¼ 9 and 2 Hz, H-9), 7.71 (d,
1H, J ¼ 9 Hz, H-12), 8.83 (d, 1H, J ¼ 2 Hz, H-11), 9.81 (d, 1H, J ¼ 9 Hz,
H-8). 13C NMR (CDCl3)
d: 27.0 (C-3Me2), 45.0 (NMe), 56.5 (OMe),
76.4 (C-3), 95.3 (C-5), 103.1 (C-14b), 113.2 (C-6a), 117.4 (C-13), 118.6
(C-7a), 119.0 (C-10), 121.4 (C-1), 123.7 (C-2), 128.9 (C-8), 129.7
(C-11a), 129.8 (C-11), 130.7 (C-7b), 131.6 (C-9), 133.0 (C-12), 144.7
(C-13a and C-14a), 158.6 (C-4a), 162.1 (C-6), 179.0 (CO). IR (KBr)
cmꢂ1: 2967, 2926, 2833, 1621, 1592, 1565, 1498, 1339, 1205, 1133,
13-one (23). 1H NMR (CDCl3)
d: 1.61 (s, 6H, C-9Me2), 1.81 (s, 6H,
C-100Me2), 2.75 (s,1H, H-300), 5.01 (d,1H, J ¼ 3.5 Hz, H-10), 5.59 (d,1H,
J ¼ 3.5 Hz, H-10), 7.15 (s, 1H, H-11), 8.00 (dd, 1H, J ¼ 9 and 2 Hz, H-2),
7.93 (d, 1H, J ¼ 9 Hz, H-5), 7.96 (d, 1H, J ¼ 2 Hz, H-4), 8.24 (d, 1H,
J ¼ 9 Hz, H-6), 10.18 (d, 1H, J ¼ 9 Hz, H-1), 12.89 (s, 1H, OH-12). 13C
1072, 1049, 876, 830, 722. UV lmax (MeOH) nm (log e): 210 (4.65),
NMR (CDCl3)
d
: 27.6 (C-9Me2), 29.8 (C-100Me2), 46.0 (C-9), 72.4
254 (4.30), 302 (4.74), 402 (3.64). MS (ESIþ) m/z: 450 and 452
[M þ H]þ, 472 and 474 [M þ Na]þ.
(C-100), 75.3 (C-300), 85.1 (C-200), 92.6 (C-10), 99.2 (C-11),104.6 (C-12a),
112.9 (C-9a), 115.3 (C-13a), 116.8 (C-6), 119.6 (C-3), 128.8 (C-1), 130.1
(C-4),130.7 (C-3b),131.0 (C-4a),132.2 (C-2),134.1 (C-5),140.6 (C-9b),
142.4 (C-6a), 156.5 (C-10), 158.4 (C-8), 160.3 (C-12), 182.4 (CO). IR
(KBr) cmꢂ1: 3267, 2992, 2958, 2854, 1667, 1626, 1498, 1385, 1339,
4.1.9. (7-Bromo-3-methoxynapht-2-yl)-[2-(7-bromo-3-methoxy-2-
naphthamido)-4,6-dimethoxyphenyl]ketone (28) and (7-bromo-3-
methoxynapht-2-yl)-(2-acetamido-4,6-dimethoxyphenyl)ketone (27)
Thionyl chloride (18.0 mL) was added to 7-bromo-3-methoxy-2-
naphthaoic acid (3.00 g, 10.7 mmol). The reaction mixture was
stirred at 65 ꢁC for 3 h and evaporated under reduced pressure to
give crude 7-bromo-3-methoxy-2-naphthaoyl chloride (26) which
was immediately used in the following step without further puri-
fication. Stannic chloride (2.1 mL, 18.3 mmol) was added to a solu-
tion of the crude 7-bromo-3-methoxy-2-naphthaoyl chloride (26)
in anhydrous dichloroethane (15 mL). The reaction mixture was
heated to 45 ꢁC for 30 min. Then, a solution of 3,5-dimethoxya-
cetanilide (14) (1.20 g, 6.11 mmol) in anhydrous dichloroethane
1138, 1087, 889, 830. UV lmax (MeOH) nm (log e): 207 (4.79), 261
(4.39), 307 (4.63), 420 (3.68). MS (ESIþ) m/z: 488 and 490 [M þ H]þ,
510 and 512 [M þ Na]þ. 3-Bromo-10,12-dihydroxy-9,9-dimethyl-8-
methylidene-8,9-dihydro-13H-benzo[a]pyrrolo[1,2,3-fg]acridin-13-
one (24). 1H NMR (DMSO-d6)
d: 1.74 (s, 6H, C-9Me2), 4.56 (d, 1H,
J ¼ 3 Hz, H-10), 4.71 (d, 1H, J ¼ 3 Hz, H-10), 6.43 (s, 1H, H-11), 7.87
(dd, 1H, J ¼ 9 and 2 Hz, H-2), 8.24 (d, 1H, J ¼ 9 Hz, H-5), 8.29 (d, 1H,
J ¼ 2 Hz, H-4), 8.35 (d, 1H, J ¼ 9 Hz, H-6), 9.95 (d, 1H, J ¼ 9 Hz, H-1),
10.51 (s,1H, OH-10),15.50 (s,1H, OH-12).13C NMR (DMSO-d6)
d: 28.1
(C-9Me2), 43.8 (C-9), 84.2 (C-10), 99.5 (C-11), 107.6 (C-12a), 107.8

1870
T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
(32 mL) was added, and the mixture was heated at 45 ꢁC for 3 h. The
reaction mixture was added to cold water (100 mL) and extracted
with dichloromethane (3 ꢃ 150 mL). The combined organic layers
were washed with an aqueous solution of potassium hydroxide
(10%) to remove excess of 7-bromo-3-methoxy-2-naphthaoic acid,
dried over MgSO4 and evaporated under reduced pressure. Column
chromatography on silica gel (CH2Cl2/MeOH: 100/0 to 99.7/0.3:
V/V) gave successively (7-bromo-3-methoxynapht-2-yl)-[2-(7-
bromo-3-methoxy-2-naphthamido)-4,6-dimethoxyphenyl]ketone
(28) (211 mg, 9%) as a yellowish amorphous solid and (7-bromo-3-
methoxynapht-2-yl)-(2-acetamido-4,6-dimethoxyphenyl)ketone
(27) (2.26 g, 81%) as an amorphous white solid. (7-Bromo-3-
methoxynapht-2-yl)-[2-(7-bromo-3-methoxy-2-naphthamido)-4,6-
55.8 (OMe-3), 88.7 (C-50), 91.9 (C-30), 104.8 (C-4), 106.0 (C-10), 117.2
(C-7), 125.1 (C-1), 128.2 (C-5), 129.7 (C-2), 129.8 (C-6), 130.1 (C-8),
132.9 (C-8a), 138.2 (C-4a), 154.2 (C-20), 155.2 (C-3), 163.9 (C-60),
165.2 (C-40), 194.2 (ArCOAr). IR (KBr) cmꢂ1: 3456, 3316, 3052, 3001,
2959, 2924, 2846, 1615, 1584, 1460, 1274, 1252, 1208, 1165, 1141. UV
lmax (MeOH) nm (log e
): 233 (4.74), 297 (4.13), 353 (3.78). MS (ESIþ)
m/z: 438 and 440 [M þ Na]þ. 4-(7-Bromo-3-methoxynapht-2-yl)-
5,7-dimethoxy-1H-quinolin-2-one (30). 1H NMR (CDCl3)
d: 3.33
(s, 3H, OMe-5), 3.80 (s, 3H, OMe-30), 3.90 (s, 3H, OMe-7), 6.13 (d, 1H,
J ¼ 2 Hz, H-6), 6.38 (s, 1H, H-3), 6.54 (d, 1H, J ¼ 2 Hz, H-8), 7.08
(s, 1H, H-40), 7.54 (s, 1H, H-10), 7.53 (dd, J ¼ 9 and 2 Hz, H-60), 7.65 (d,
1H, J ¼ 9 Hz, H-50), 7.93 (d, 1H, J ¼ 2 Hz, H-80), 12.40 (s, 1H, NH). 13C
NMR (CDCl3) d
: 55.4 (OMe-5), 55.6 (OMe-30), 55.8 (OMe-7), 91.3
dimethoxyphenyl]ketone (28). 1H NMR (CDCl3)
d
: 3.35 (s, 3H,
(C-8), 94.9 (C-6), 103.8 (C-40), 106.2 (C-4a), 117.3 (C-70), 118.9 (C-3),
126.1 (C-10), 128.1 (C-50), 129.6 (C-60), 129.7 (C-8a0), 129.8 (C-80),
132.8 (C-4a0), 134.9 (C-20), 141.6 (C-8a), 149.2 (C-4), 156.3 (C-30),
158.5 (C-5), 162.5 (C-7), 164.4 (C-2). IR (KBr) cmꢂ1: 3353, 3000,
2923, 2849, 1655, 1623, 1602, 1400, 1386, 1205, 978, 814. UV lmax
OMe-60), 3.81 (s, 3H, OMe-3), 3.96 (s, 3H, OMe-40), 4.17 (s, 3H, OMe-
300), 6.18 (d, 1H, J ¼ 2 Hz, H-50), 7.08 (s, 1H, H-4), 7.20 (s, 1H, H-400),
7.54 (dd, 1H, J ¼ 9 and 2 Hz, H-6), 7.57 (dd, H, J ¼ 9 and 2 Hz, H-600),
7.60 (d, 1H, J ¼ 9 Hz, H-5), 7.62 (d, 1H, J ¼ 9 Hz, H-500), 7.79 (s, 1H, H-
1), 7.94 (d, 1H, J ¼ 2 Hz, H-8), 8.03 (d, 1H, J ¼ 2 Hz, H-800), 8.24 (d, H,
J ¼ 2 Hz, H-30), 8.62 (s, 1H, H-100), 12.10 (s, 1H, NH). 13C NMR (CDCl3)
(MeOH) nm (log e): 234 (4.86), 262 (4.43), 324 (4.08), 336 (4.03). MS
(ESIþ) m/z: 440 and 442 [M þ H]þ, 462 and 464 [M þ Na]þ, 478 and
d
: 56.6 (OMe-60), 55.8 (OMe-40), 55.9 (OMe-3), 56.0 (OMe-300), 95.0
480 [M þ K]þ.
(C-50), 98.8 (C-30), 105.5 (C-4), 106.5 (C-400), 112.3 (C-10), 117.6 (C-7),
118.0 (C-700), 125.0 (C-4a00), 127.9 (C-500), 128.0 (C-1), 128.2 (C-5),
129.3 (C-2 and C0-0200), 130.6 (C-8), 130.8 (C-6), 131.0 (C-800), 131.7
(C-600), 132.9 (C-1 ), 133.8 (C-8a), 134.5 (C-8a00), 135.7 (C-4a), 141.6
(C-20), 155.2 (C-300), 155.6 (C-3), 161.6 (C-60), 164.3 (C-40), 164.4
(CONH), 195.0 (ArCOAr). IR (KBr) cmꢂ1: 3282, 3003, 2920, 2850,
1669, 1609, 1575, 1526, 1447, 1305, 1260, 1208, 1157, 1059, 844, 726.
4.1.11. (7-Bromo-3-methoxynapht-2-yl)-(2-amino-4,6-
dimethoxyphenyl)ketone (31)
An aqueous solution of hydrochloric acid (20 mL, 35%) was
added to a solution of (7-bromo-3-methoxynapht-2-yl)-(2-acet-
amido-4,6-dimethoxyphenyl)ketone (27) (2.26 g, 4.83 mmol) in
methanol (30 mL). The reaction mixture was heated to reflux for
4 h. After dilution with cold water (100 mL), an aqueous solution of
sodium hydroxide (20%) was added to obtain pH ¼ 10. An extrac-
tion was performed with ethyl acetate (3 ꢃ 150 mL). The combined
organic layers were dried over MgSO4, filtered and evaporated
under reduced pressure to give (7-bromo-3-methoxynapht-2-yl)-
(2-amino-4,6-dimethoxyphenyl)ketone (31) (1.9 g, 92%).
UV lmax (MeOH) nm (log e
): 201 (4.46), 234 (4.83). MS (ESIþ) m/z:
700, 702 and 704 [M þ Na]þ, 716, 718 and 720 [M þ K]þ. (7-Bromo-
3-methoxynapht-2-yl)-(2-acetamido-4,6-dimethoxyphenyl)ketone
(27). 1H NMR (CDCl3) : 2.23 (s, 1H, COMe), 3.28 (s, 3H, OMe-60),
d
3.83 (s, 3H, OMe-3), 3.90 (s, 3H, OMe-40), 6.07 (d, 1H, J ¼ 2 Hz, H-50),
7.08 (s, 1H, H-4), 7.53 (dd, 1H, J ¼ 9 and 2 Hz, H-6), 7.60 (d, 1H,
J ¼ 9 Hz, H-5), 7.61 (s, 1H, H-1), 7.91 (d, 1H, J ¼ 2 Hz, H-8), 8.03
(d, 1H, J ¼ 2 Hz, H-30), 11.50 (s, 1H, NH). 13C NMR (CDCl3)
d
: 25.8
4.1.12. 9-Bromo-1,3-dimethoxybenzo[b]acridin-12(5H)-one (29)
A solution of (7-bromo-3-methoxynapht-2-yl)-(2-amino-4,6-
dimethoxyphenyl)ketone (31) (1.60 g, 3.84 mmol) in anhydrous
N,N-dimethylformamide (40 mL) was added to a suspension of
sodium hydride (19.2 mmol) in anhydrous N,N-dimethylformamide
(20 mL). The reaction mixture was stirred at room temperature for
12 h. A hot filtration on Büchner funnel permitted to remove
sodium salts. Then, after addition of cold water (300 mL), the
precipitate was filtered, washed with water (3 ꢃ 50 mL), with
methanol (50 mL) and, to finish, with ethyl acetate (2 ꢃ 50 mL). A
yellow amorphous solid corresponding to 9-bromo-1,3-dimethox-
ybenzo[b]acridin-12(5H)-one (29) (1.18 g, 80%) was obtained and
used in the following step without further purification. 1H NMR
(COMe), 56.8 (OMe-60, OMe-40 and OMe-3), 94.3 (C-50), 97.0 (C-30),
105.2 (C-4), 109.1 (C-1’), 117.6 (C-7), 126.8 (C-1), 128.2 (C-5), 129.4
(C-2), 130.4 (C-8), 130.7 (C-6), 133.5 (C-8a), 136.4 (C-4a), 143.6
(C-20), 155.2 (C-3), 161.8 (C-60), 164.3 (C-40), 169.9 (CONH), 198.0
(ArCOAr). IR (KBr) cmꢂ1: 3289, 2920, 2850, 1609, 1582, 1446, 1303,
1252, 1206, 1159, 849. UV lmax (MeOH) nm (log e): 203 (4.33), 206
(4.37), 234 (4.80), 285 (4.12), 312 (4.18). MS (ESIþ) m/z: 480 and 482
[M þ Na]þ.
4.1.10. (7-Bromo-3-methoxynapht-2-yl)-(2-amino-4,6-
dimethoxyphenyl)ketone (31) and 4-(7-bromo-3-methoxynapht-2-
yl)-5,7-dimethoxy-1H-quinolin-2-one (30)
A solution of (7-bromo-3-methoxynapht-2-yl)-(2-acetamido-
4,6-dimethoxyphenyl)ketone (27) (109 mg, 0.237 mmol) in anhy-
drous N,N-dimethylformamide (6 mL) was added to sodium
hydride (1.63 mmol). The reaction mixture was stirred at room
temperature for 2 days and poured on cold water (50 mL). The
precipitate was filtered and dried in a vacuum over P2O5. Column
chromatography on silica gel (CH2Cl2/MeOH: 100/0 to 99.2/0.8:
V/V) gave (7-bromo-3-methoxynapht-2-yl)-(2-amino-4,6-dime-
thoxyphenyl)ketone (31) (10 mg, 10%) as an amorphous yellow
solid and 4-(7-bromo-3-methoxynapht-2-yl)-5,7-dimethoxy-1H-
quinolin-2-one (30) (50.7 mg, 50%) as an amorphous white solid.
(7-Bromo-3-methoxynapht-2-yl)-(2-amino-4,6-dimethoxyphenyl)
(DMSO-d6) d: 3.84 (s, 3H, OMe), 3.88 (s, 3H, OMe), 6.24 (d, 1H,
J ¼ 2 Hz, H-4), 6.45 (d, J ¼ 2 Hz, H-2), 7.61 (dd, 1H, J ¼ 9 and 2 Hz, H-
8), 7.76 (s, 1H, H-6), 7.92 (d, 1H, J ¼ 9 Hz, H-7), 8.39 (d, 1H, J ¼ 2 Hz,
H-10), 8.72 (s, 1H, H-11), 11.36 (s, 1H, NH). IR (KBr) cmꢂ1: 3280,
3125, 2991, 2922, 1628, 1596, 1507, 1216, 1168, 1127. UV lmax
(MeOH) nm (log e): 209 (4.24), 212 (4.24), 227 (4.25), 248 (4.21),
381 (4.75), 324 (4.05), 431 (3.70). MS (ESIþ) m/z: 384 and 386
[M þ H]þ.
4.1.13. 9-Bromo-1,3-dihydroxybenzo[b]acridin-12(5H)-one (32)
An aqueous solution of bromhydric acid (20 mL, 48%) was added
to a solution of 9-bromo-1,3-dimethoxybenzo[b]acridin-12(5H)-
one (29) (400 mg, 1.04 mmol). The reaction mixture was heated to
110 ꢁC for 48 h. An aqueous solution of sodium hydroxide (10%) was
added to obtain pH ¼ 4. The solid was filtered, washed with water
(3 ꢃ100 mL), dried in vacuum under P2O5, and to finish, was washed
with dichloromethane (3 ꢃ 50 mL). 9-Bromo-1,3-dihydroxybenzo
ketone (31). 1H NMR (CDCl3) : 3.22 (s, 3H, OMe-60), 3.82 (s, 3H,
d
OMe-40), 3.86 (s, 3H, OMe-3), 5.63 (d, 1H, J ¼ 2 Hz, H-50), 5.79 (d, H,
J ¼ 2 Hz, H-30), 6.50 (s, 2H, NH2), 7.08 (s, 1H, H-4), 7.50 (dd, 1H, J ¼ 9
and 2 Hz, H-6), 7.51 (s, 1H, H-1), 7.60 (d, 1H, J ¼ 9 Hz, H-5), 7.98
(d, 1H, J ¼ 2 Hz, H-8). 13C NMR (CDCl3)
d
: 55.3 (OMe-60 and OMe-40),

T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
1871
[b]acridin-12(5H)-one (32) was obtained as a brown amorphous
solid (350 mg, 94%).1H NMR (DMSO-d6)
6.28 (d, J ¼ 2 Hz, H-4), 7.66 (dd,1H, J ¼ 9 and 2 Hz, H-8), 7.85 (s,1H, H-
6), 7.96 (d, 1H, J ¼ 9 Hz, H-7), 8.44 (d, 1H, J ¼ 2 Hz, H-10), 8.85 (s, 1H,
H-11), 10.71 (s, 1H, OH-3), 11.71 (s, 1H, NH), 13.97 (s, 1H, OH-1). 13C
UV lmax (MeOH) nm (log
e
): 214 (4.40), 253 (4.36), 276 (4.78), 300
d
: 5.97 (d,1H, J ¼ 2 Hz, H-2),
(4.74), 315 (4.64), 372 (3.85), 468 (3.60). MS (ESIþ) m/z: 422 and 424
[M þ H]þ, 444 and 446 [M þ Na]þ.
4.1.15. 10-Bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-
benzo[b]pyrano[3,2-h]acridin-7-one (25) and 10-bromo-6-
hydroxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]
acridin-7-one (36)
Anhydrous sodium carbonate (1.67 g, 10.0 mmol) and methyl
iodide (495 mL,10.0 mmol) were added to a solution of 10-bromo-6-
NMR (DMSO-d6) d: 91.5 (C-4), 95.6 (C-2), 102.6 (C-12a), 112.2 (C-6),
117.4 (C-9), 121.0 (C-11a), 126.4 (C-11), 129.1 (C-10a), 129.3 (C-7),
131.5 (C-10), 132.0 (C-8), 134.7 (C-6a), 138.3 (C-5a), 144.9 (C-4a),
164.6 (C-1), 165.8 (C-3), 181.1 (C-12). IR (KBr) cmꢂ1: 3278, 3055,
2920, 1650, 1588, 1505, 1174, 1022, 1001, 817. UV lmax (MeOH) nm
(log
e
): 207 (3.90), 224 (3.61), 284 (4.67), 355 (3.41), 369 (3.14), 453
hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]
acridin-7-one (34) (423 mg, 1.00 mmol) in anhydrous N,N-dime-
thylformamide (22 mL). The reaction mixture was heated to 50 ꢁC
for 27 h. Then, a suspension of sodium hydride (10 mmol) in
anhydrous N,N-dimethylformamide (5 mL) and methyl iodide
(3.58). MS (ESIþ) m/z: 356 and 358 [M þ H]þ.
4.1.14. 9-Bromo-5-hydroxy-1,1-dimethyl-2-methyliden-1,2-
dihydrobenzo[b]furo[3,2-h]acridin-6(13H)-one (35) and 10-bromo-
6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]
acridin-7-one (34)
Anhydrous potassium carbonate (643 mg, 4.66 mmol), anhy-
drous potassium iodide (774 mg, 4.66 mmol) and 3-chloro-3-
(495
mL, 10.0 mmol) were added, and the reaction mixture was
heated at 40 ꢁC for more 3 h. After addition of water (100 mL) and
extraction with dichloromethane (3 ꢃ 100 mL), the combined
organic layers were dried over MgSO4, filtered and evaporated
under reduced pressure. Column chromatography on silica gel
(CH2Cl2/MeOH: 100/0 to 99.7/0.3: V/V) gave 10-bromo-6-hydroxy-
3,3,14-trimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]acridin-
7-one (36) (51 mg, 12%) as a red amorphous solid and 10-bromo-6-
methoxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]
acridin-7-one (25) (371 mg, 82%) as a yellow amorphous solid. 10-
Bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo[b]pyr-
methylbut-1-yne (523 mL, 4.66 mmol) were added to a solution of
9-bromo-1,3-dihydroxybenzo[b]acridin-12(5H)-one (32) (553 mg,
1.55 mmol) in anhydrous N,N-dimethylformamide (50 mL). The
reaction mixture was stirred at 65 ꢁC for 25 h, poured in water
(150 mL) and then, extracted with dichloromethane/methanol:
10/1: V/V (4 ꢃ 200 mL). The combined organic layers were dried over
MgSO4, filtered and evaporated under reduced pressure. Column
chromatography on silica gel (CH2Cl2/C6H12: 50/50 to 100/0: V/V)
gave successively 9-bromo-5-hydroxy-1,1-dimethyl-2-methyliden-
1,2-dihydrobenzo[b]furo[3,2-h]acridin-6(13H)-one (35) (26 mg, 4%)
as an orange amorphous solid, and a mixture of 9-bromo-1-
hydroxy-3-(1,1-dimethylpropyn-1-oxy)benzo[b]acridin-12(5H)-
one (33) and 10-bromo-6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-
benzo[b]pyrano[3,2-h]acridin-7-one (34). Without any further
purification, the mixture of compound 33 and 34 was dissolved in
anhydrous N,N-dimethylformamide (10 mL). The solution was
heated to 130 ꢁC for 3.5 h, and poured on cold water (80 mL). The
solid was filtered, washed with water (3 ꢃ 20 mL) and dried in
a vacuum over P2O5 to give 10-bromo-6-hydroxy-3,3-dimethyl-
3,14-dihydro-7H-benzo[b]pyrano[3,2-h]acridin-7-one (34) (249 mg,
38%) as a red amorphous solid. 9-Bromo-5-hydroxy-1,1-dimethyl-2-
methyliden-1,2-dihydrobenzo[b]furo[3,2-h]acridin-6(13H)-one (35).
ano[3,2-h]acridin-7-one (25). 1H NMR (CDCl3)
d: 1.56 (s, 6H,
C-3Me2), 3.90 (s, 3H, NMe), 4.01 (s, 3H, OMe), 5.55 (d, 1H, J ¼ 10 Hz,
H-2), 6.31 (s, 1H, H-5), 6.57 (d, 1H, J ¼ 10 Hz, H-1), 7.57 (dd, 1H, J ¼ 9
and 2 Hz, H-11), 7.62 (s, 1H, H-13), 7.72 (d, 1H, J ¼ 9 Hz, H-12), 8.16
(d, 1H, J ¼ 2 Hz, H-9), 8.81 (s, 1H, H-8). 13C NMR (CDCl3)
d: 27.0
(C-3Me2), 44.8 (NMe), 56.5 (OMe), 76.6 (C-3), 94.2 (C-5), 103.2
(C-14b), 109.7 (C-6a), 112.1 (C-13), 118.1 (C-10), 121.9 (C-1), 123.3
(C-2), 126.2 (C-7a), 127.3 (C-8), 128.5 (C-12), 129.5 (C-8a), 131.3
(C-9), 131.6 (C-11), 134.1 (C-12a), 142.3 (C-13a), 147.4 (C-14a), 160.1
(C-4a), 163.3 (C-6), 177.8 (C]O). IR (KBr) cmꢂ1: 3058, 3006, 2969,
2953, 2921, 1645, 1633, 1614, 1583, 1559, 1489, 1458, 1197, 1139,
1120, 1088, 854, 805, 768. UV lmax (MeOH) nm (log e): 211 (4.54),
245 (4.36), 279 (4.73), 300 (4.72), 310 (4.73), 366 (3.87), 450 (3.72).
MS (ESIþ) m/z: 472 and 474 [M þ Na]þ, 488 and 490 [M þ K]þ. 10-
Bromo-6-hydroxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo[b]pyrano
1H NMR (DMSO-d6)
d: 1.71 (s, 6H, C-1Me2), 4.56 (d, 1H, J ¼ 3 Hz,
[3,2-h]acridin-7-one (36). 1H NMR (CDCl3)
d: 1.57 (s, 6H, C-3Me2),
CH2a), 4.70 (d,1H, J ¼ 3 Hz, CH2b), 6.31 (s,1H, H-4), 7.70 (dd,1H, J ¼ 2
and 9 Hz, H-10), 7.94 (d,1H, J ¼ 9 Hz, H-11), 8.49 (d,1H, J ¼ 2 Hz, H-8),
8.53 (s,1H, H-12), 8.91 (s,1H, H-7),10.15 (s,1H, NH),14.74 (s,1H, OH).
4.00 (s, 3H, NMe), 5.58 (d, 1H, J ¼ 10 Hz, H-2), 6.28 (s, 1H, H-5), 6.60
(d, 1H, J ¼ 10 Hz, H-1), 7.65 (dd, 1H, J ¼ 9 and 2 Hz, H-11), 7.74 (s, 1H,
H-13), 7.80 (d, 1H, J ¼ 9 Hz, H-12), 8.19 (d, 1H, J ¼ 2 Hz, H-9), 8.89 (s,
13C NMR (DMSO-d6)
d: 27.8 (C-1Me2), 43.5 (C-1), 84.4 (CH2), 90.9
1H, H-8), 14.48 (s, 1H, OH). 13C NMR (DMSO-d6)
d: 27.1 (C-3Me2),
(C-4), 104.3 (C-5a), 107.7 (C-13b), 114.2 (C-12), 118.1 (C-9), 120.8
(C-6a), 126.4 (C-7), 129.5 (C-7a), 129.7 (C-11), 131.7 (C-8), 132.2
(C-10),134.8 (C-11a),138.1 (C-12a),138.9 (C-13a),162.7 (C-3a),165.8
(C-5), 172.6 (C-2), 182.4 (C]O). IR (KBr) cmꢂ1: 3400, 2960, 2921,
2865, 1645, 1594, 1507, 1497, 1470, 1283, 1162, 1141, 1077, 855, 824,
44.2 (NMe), 76.8 (C-3), 97.8 (C-5), 101.3 (C-14b), 112.5 (C-13), 118.7
(C-10), 121.6 (C-1), 122.8 (C-7a), 123.4 (C-2), 126.7 (C-8), 128.7
(C-12), 129.3 (C-8a), 131.2 (C-9), 132.3 (C-11), 134.7 (C-12a), 142.1
(C-13a), 145.3 (C-14a), 162.5 (C-4a), 165.7 (C-6), 181.8 (C-7). IR (KBr)
cmꢂ1: 3425, 3057, 2975, 1629, 1590, 1578, 1467, 1388, 1375, 1329,
812. UV lmax (MeOH) nm (log
e
): 204 (4.48), 231 (4.29), 265 (4.54),
1274, 1173, 1127, 866, 819. UV lmax (MeOH) nm (log e): 211 (4.40),
288 (4.81), 358 (4.05), 459 (3.59). MS (ESIþ) m/z: 422 and 424
[M þ H]þ, 444 and 446 [M þ Na]þ, 460 and 462 [M þ K]þ.10-Bromo-
6-hydroxy-3,3-dimethyl-3,14-dihydro-7H-benzo[b]pyrano[3,2-h]
253 (4.24), 279 (4.60), 312 (4.67), 377 (3.84), 468 (3.57). MS (ESIþ)
m/z: 436 and 438 [M þ H]þ, 458 and 460 [M þ Na]þ, 472 and 474
[M þ K]þ.
acridin-7-one (34). 1H NMR (DMSO-d6)
d: 1.45 (s, 6H, C-3Me2), 5.77
(d, 1H, J ¼ 10 Hz, H-2), 6.05 (s, 1H, H-5), 7.13 (d, 1H, J ¼ 10 Hz, H-1),
7.69 (dd, 1H, J ¼ 9 and 2 Hz, H-11), 7.98 (d, 1H, J ¼ 9 Hz, H-12), 8.21
(s, 1H, H-13), 8.48 (d, 1H, J ¼ 2 Hz, H-9), 8.89 (s, 1H, H-8), 11.15 (s, 1H,
4.1.16. (ꢀ)-cis-10-Bromo-1,2-dihydroxy-6-methoxy-3,3,14-
trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyrano[3,2-h]acridin-7-
one (37)
NH), 14.42 (s, 1H, OH). 13C NMR (DMSO-d6)
d: 28.1 (C-3Me2), 77.9
10-Bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo
(C-3), 96.3 (C-5), 98.5 (C-14b), 103.4 (C-6a), 113.6 (C-13), 116.6 (C-1),
117.9 (C-10),120.8 (C-7a),126.3 (C-8),126.4 (C-2),129.5 (C-8a),129.6
(C-12), 131.6 (C-9), 132.1 (C-11), 134.7 (C-12a), 138.3 (C-13a), 139.2
(C-14a), 160.8 (C-4a), 164.8 (C-6), 181.9 (C]O). IR (KBr) cmꢂ1: 3388,
2960, 2929, 1647, 1587, 1552, 1498, 1345, 1278, 1166, 1126, 863, 820.
[a]pyrano[3,2-h]acridin-7-one (9) (100 mg, 222
a solution of osmium tetroxide (2.5% m/V in t-BuOH) (240
N-methylmorpholine N-oxide hydrate (380 mg, 2.80 mmol) in
t-BuOH/THF/H2O: 10/3/1: V/V/V (3 mL). The reaction mixture was
stirred at room temperature for 3.25 h. After addition of saturated
m
mol) was added to
mL) and

1872
T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
aqueous NaHSO3 (5 mL), the reaction was stirred for 1 h and then
extracted with dichloromethane (3 ꢃ 15 mL). The combined org-
anic layers were dried over MgSO4, filtered and evaporated under
reduced pressure. Column chromatography on silica gel (CH2Cl2/
MeOH: 100/0 to 97/3: V/V) gave (ꢀ)-cis-10-bromo-1,2-dihydroxy-
6-methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyr-
ano[3,2-h]acridin-7-one (37) (69.2 mg, 64%) as a yellowish amor-
a vacuum over P2O5 to give (ꢀ)-cis-1,2-diacetoxy-10-bromo-6-
methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyrano
[3,2-h]acridin-7-one (39) (32 mg, 93%) as a yellowish amorphous
solid. 1H NMR (CDCl3)
d: 1.48 (s, 3H, C-3Me2B), 1.58 (s, 3H,
C-3Me2A), 1.98 (s, 3H, MeCOC-1), 2.03 (s, 3H, MeCOC-2), 3.71 (s, 3H,
NMe), 4.05 (s, 3H, OMe), 5.46 (d, 1H, J ¼ 5 Hz, H-2), 6.39 (s, 1H, H-5),
6.54 (d, 1H, J ¼ 5 Hz, H-1), 7.42 (d, 1H, J ¼ 9 Hz, H-13), 7.72 (dd, 1H,
J ¼ 9 and 2 Hz, H-9), 7.91 (d, 1H, J ¼ 9 Hz, H-12), 7.97 (d, 1H, J ¼ 2 Hz,
phous solid. 1H NMR (DMSO-d6)
d: 1.38 (s, 3H, C-3Me2A),1.42 (s, 3H,
C-3Me2B), 3.66 (t, 1H, J ¼ 5 Hz, H-2), 3.83 (s, 3H, OMe), 3.93 (s, 3H,
NMe), 4.63 (d, 1H, J ¼ 9 Hz, OH-1), 5.05 (d, 1H, J ¼ 5 Hz, OH-2), 5.07
(dd, 1H, J ¼ 9 and 5 Hz, H-1), 6.27 (s, 1H, H-5), 7.72 (dd, 1H, J ¼ 9 and
2 Hz, H-9), 7.81 (d, 1H, J ¼ 9 Hz, H-13), 8.12 (d, 1H, J ¼ 9 Hz, H-12),
8.22 (d, 1H, J ¼ 2 Hz, H-11), 9.12 (d, 1H, J ¼ 9 Hz, H-8). 13C NMR
H-11), 9.72 (d, 1H, J ¼ 9 Hz, H-8). 13C NMR (CDCl3)
d: 20.8 (MeCOC-
2), 21.0 (MeCOC-1), 23.4 (C-3Me2A), 24.5 (C-3Me2B), 42.9 (NMe),
56.5 (OMe), 65.6 (C-1), 69.6 (C-2), 76.4 (C-3), 95.9 (C-5), 97.8
(C-14b), 115.0 (C-6a), 117.2 (C-13), 119.2 (C-10), 119.4 (C-7a), 128.7
(C-8), 129.6 (C-11a), 129.9 (C-11), 130.8 (C-7b), 131.9 (C-9), 133.3
(C-12), 145.2 (C-13a), 147.5 (C-14a), 159.2 (C-4a), 162.1 (C-6), 170.6
(MeCOC-2), 171.1 (MeCOC-1), 179.0 (CO). IR (KBr) cmꢂ1: 2978, 2931,
1750, 1622, 1596, 1504, 1231, 1211, 1154, 1070, 908, 887, 831. UV lmax
(DMSO-d6) d: 22.8 (C-3Me2A), 25.5 (C-3Me2B), 42.5 (NMe), 56.4
(OMe), 64.2 (C-1), 70.6 (C-2), 78.1 (C-3), 95.5 (C-5), 103.9 (C-14b),
114.0 (C-6a), 117.7 (C-7a), 118.0 (C-10), 119.3 (C-13), 128.3 (C-8),
129.5 (C-11a), 130.4 (C-11), 130.7 (C-7b), 131.2 (C-9), 133.0 (C-12),
145.0 (C-13a), 147.3 (C-14a), 158.8 (C-4a), 160.5 (C-6), 177.8 (CO). IR
(KBr) cmꢂ1: 3445, 3378, 2972, 2931, 2849, 1627, 1596, 1509, 1386,
(MeOH) nm (log e): 206 (4.65), 252 (4.45), 296 (4.72), 379 (3.73),
396 (3.75). MS (ESIþ) m/z: 568 and 570 [M þ H]þ.
1211, 1147, 1072, 1052, 889, 838, 815. UV lmax (MeOH) nm (log
e
):
4.1.19. (ꢀ)-cis-1,2-Diacetoxy-10-bromo-6-methoxy-3,3,14-
trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2-h]acridin-7-
one (40)
The procedure described for the preparation of 39 from 37,
applied to (ꢀ)-cis-10-bromo-1,2-dihydroxy-6-methoxy-3,3,14-tri-
methyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2-h]acridin-7-
205 (4.68), 254 (4.48), 298 (4.76), 383 (3.75), 400 (3.76). MS (ESIþ)
m/z: 484 and 486 [M þ H]þ, 506 and 508 [M þ Na]þ.
4.1.17. (ꢀ)-cis-10-Bromo-1,2-dihydroxy-6-methoxy-3,3,14-
trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2-h]acridin-7-
one (38)
one (38) (35 mg, 72
m
mol) gave (ꢀ)-cis-1,2-diacetoxy-10-bromo-6-
10-Bromo-6-methoxy-3,3,14-trimethyl-3,14-dihydro-7H-benzo
methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano
[3,2-h]acridin-7-one (40) (40 mg, 98%) as a yellow amorphous
[b]pyrano[3,2-h]acridin-7-one (25) (100 mg, 222
mmol) was added
to a solution of osmium tetroxide (2.5% m/V in t-BuOH) (250
mL)
product. 1H NMR (CDCl3)
d: 1.50 (s, 3H, C-3MeB), 1.59 (s, 3H,
and N-methylmorpholine N-oxide hydrate (90 mg, 0.667 mmol) in
CH2Cl2/MeOH: 4/1: V/V (8 mL). The reaction mixture was stirred at
room temperature for 4.25 h. After addition of saturated aqueous
NaHSO3 (5 mL), the reaction was stirred for 1 h and then extracted
with dichloromethane (3 ꢃ 100 mL). The combined organic layers
were dried over MgSO4, filtered and evaporated under reduced
pressure. Column chromatography on silica gel (CH2Cl2/MeOH:
100/0 to 98/2: V/V) gave (ꢀ)-cis-10-bromo-1,2-dihydroxy-6-
methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano
[3,2-h]acridin-7-one (38) (104.6 mg, 97%) as a yellow amorphous
C-3MeA), 1.99 (s, 3H, MeCOC-1), 2.05 (s, 3H, MeCOC-2), 3.72 (s, 3H,
NMe), 4.03 (s, 3H, OMe), 5.50 (d, 1H, J ¼ 5 Hz, H-2), 6.33 (s, 1H, H-5),
6.58 (d, 1H, J ¼ 5 Hz, H-1), 7.52 (s, 1H, H-13), 7.61 (dd, 1H, J ¼ 9 and
2 Hz, H-11), 7.74 (d, 1H, J ¼ 9 Hz, H-12), 8.19 (d, 1H, J ¼ 2 Hz, H-9),
8.79 (s, 1H, H-8). 13C NMR (CDCl3)
d: 20.8 (MeCOC-2), 21.2 (MeCOC-
1), 23.6 (C-3MeA), 24.6 (C-3MeB), 43.1 (NMe), 56.5 (OMe), 65.8
(C-1), 69.5 (C-2), 76.6 (C-3), 94.8 (C-5), 98.1 (C-14b), 111.4 (C-6a),
111.9 (C-13), 118.3 (C-10), 126.6 (C-7a), 127.2 (C-8), 128.5 (C-12),
129.7 (C-8a), 131.4 (C-9), 131.7 (C-11), 134.2 (C-12a), 142.8 (C-13a),
150.3 (C-14a), 160.5 (C-4a), 163.0 (C-6), 170.6 (MeCOC-2), 171.1
(MeCOC-1), 178.1 (C]O). IR (KBr) cmꢂ1: 3054, 2975, 2921, 2848,
1746, 1643, 1614, 1590, 1493, 1396, 1236, 1197, 1155, 1084, 1026, 913,
solid. 1H NMR (DMSO-d6)
d: 1.39 (s, 3H, C-3MeA), 1.43 (s, 3H,
C-3MeB), 3.68 (t, 1H, J ¼ 5 Hz, H-2), 3.82 (s, 3H, OMe), 3.89 (s, 3H,
NMe), 4.64 (d, 1H, J ¼ 10 Hz, OH-1), 5.08 (dd, 1H, J ¼ 10 and 5 Hz, H-
1), 5.10 (d, 1H, J ¼ 5 Hz, OH-2), 6.20 (s, 1H, H-5), 7.66 (dd, 1H, J ¼ 9
and 2 Hz, H-11), 7.95 (s, 1H, H-13), 8.00 (d, 1H, J ¼ 9 Hz, H-12), 8.41
703. UV lmax (MeOH) nm (log e): 208 (4.48), 245 (4.26), 288 (4.80),
334 (3.97), 440 (3.68). MS (ESIþ) m/z: 568 and 570 [M þ H]þ, 590
and 592 [M þ Na]þ.
(d, 1H, J ¼ 2 Hz, H-9), 8.64 (s, 1H, H-8). 13C NMR (DMSO-d6)
d: 22.8
(C-3MeB), 25.6 (C-3MeA), 42.3 (NMe), 56.3 (OMe), 64.5 (C-1), 70.6
(C-2), 78.3 (C-3), 94.1 (C-5), 104.1 (C-14b), 110.3 (C-6a), 112.8 (C-13),
117.5 (C-10), 126.2 (C-8), 126.3 (C-7a), 129.1 (C-8a), 129.7 (C-12),
131.3 (C-9 and C-11), 134.3 (C-12a), 142.5 (C-13a), 150.3 (C-14a),
160.3 (C-4a), 161.7 (C-6), 176.8 (C]O). IR (KBr) cmꢂ1: 3361, 2956,
2925, 2851, 1633, 1606,1590,1501,1458,1388,1205,1143, 1092, 816.
4.1.20. (ꢀ)-cis-10-Bromo-1,2-di-O-carbonyl-1,2-dihydroxy-6-
methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyrano
[3,2-h]acridin-7-one (41)
N,N0-Carbonydiimidazole (54 mg, 333
mmol) was added to
a solution of (ꢀ)-cis-10-bromo-1,2-dihydroxy-6-methoxy-3,3,14-
trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyrano[3,2-h]acridin-7-
UV lmax (MeOH) nm (log
e
): 208 (4.45), 240 (4.26), 286 (4.82), 335
one (37) (29.5 mg, 60.9 mmol) in 2-butanone (2 mL). The reaction
(3.95), 446 (3.67). MS (ESIþ) m/z: 506 and 508 [M þ Na]þ, 522 and
mixture was stirred at room temperature for 5 h and water (5 mL)
was added. An extraction with dichloromethane (3 ꢃ 10 mL) was
performed and the combined organic layers were dried over
MgSO4, filtered and evaporated under reduced pressure. Column
chromatography on silica gel (CH2Cl2/MeOH: 100/0 to 99.4/0.6:
V/V) gave (ꢀ)-cis-10-bromo-1,2-di-O-carbonyl-1,2-dihydroxy-6-
methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyrano
[3,2-h]acridin-7-one (41) (29 mg, 93%) as a yellowish amorphous
524 [M þ K]þ.
4.1.18. (ꢀ)-cis-1,2-Diacetoxy-10-bromo-6-methoxy-3,3,14-
trimethyl-1,2,3,14-tetrahydro-7H-benzo[a]pyrano[3,2-h]acridin-7-
one (39)
Acetic anhydride (284
mL, 3.02 mmol) and 4-dimethylamino-
pyridine (1 mg) were added to a solution of (ꢀ)-cis-10-bromo-1,2-
dihydroxy-6-methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-
solid. 1H NMR (CDCl3)
d: 1.46 (s, 3H, C-3Me2B), 1.63 (s, 3H,
benzo[a]pyrano[3,2-h]acridin-7-one (37) (29.2 mg, 60.3
m
mol) in
C-3Me2B), 3.96 (s, 3H, NMe), 4.03 (s, 3H, OMe), 4.82 (d, 1H, J ¼ 8 Hz,
H-2), 6.27 (d, 1H, J ¼ 8 Hz, H-1), 6.38 (s, 1H, H-5), 7.53 (d, 1H,
J ¼ 9 Hz, H-13), 7.72 (dd, 1H, J ¼ 9 and 2 Hz, H-9), 7.92 (d, 1H,
J ¼ 9 Hz, H-12), 7.98 (d, 1H, J ¼ 2 Hz, H-11), 9.62 (d, 1H, J ¼ 9 Hz,
anhydrous pyridine (2.0 mL). The reaction mixture was stirred for
24 h at room temperature. After addition of cold water (5 mL), the
precipitate was filtered, washed with water (2 ꢃ 5 mL) and dried in

T. Gaslonde et al. / European Journal of Medicinal Chemistry 46 (2011) 1861e1873
1873
H-8). 13C NMR (CDCl3)
d: 22.1 (C-3Me2B), 24.4 (C-3Me2A), 43.9
and other biological properties of acronycine, J. Pharm. Sci. 55 (1966)
758e768.
(NMe), 56.6 (OMe), 70.9 (C-1), 74.1 (C-3), 78.8 (C-2), 96.4 (C-5), 97.2
(C-14b), 115.1 (C-6a), 117.7 (C-13), 119.5 (C-10), 119.9 (C-7a), 128.5
(C-8), 129.1 (C-11a), 130.0 (C-11), 130.9 (C-7b), 132.0 (C-9), 133.2
(C-12), 145.4 (C-13a), 147.3 (C-14a), 153.6 (OCOO), 158.4 (C-4a),
162.8 (C-6), 179.2 (CO). IR (KBr) cmꢂ1: 3023, 2980, 2937, 2851, 1812,
1625, 1594, 1501, 1396, 1174, 1143, 1050, 828. UV lmax (MeOH) nm
[4] J.H. Scarffe, A.R. Beaumont, D. Crowther, Phase I-II evaluation of acronycine in
patients with multiple myeloma, Canc. Treat. Rep. 67 (1983) 93e94.
[5] T.-L. Su, K.A. Watanabe, Anticancer Acridone alkaloids. in: Atta-ur- Rahman,
F.Z. Basha (Eds.), Studies in Natural Products Chemistry, Vol. 13. Elsevier,
Amsterdam, 1993, pp. 347e382.
[6] T.-C. Chou, C.-C. Tzeng, T.-S. Wu, K.A. Watanabe, T.-L. Su, Inhibition of cell
growth and macromolecule biosynthesis of human promyelocytic leukemic
cells by acridone alkaloids, Phytother. Res. 3 (1989) 237e242.
[7] A. Elomri, S. Michel, M. Koch, E. Seguin, F. Tillequin, A. Pierré, Gh. Atassi,
Synthesis and cytotoxic activity of 11-nitro and 11-amino derivatives of
acronycine and 6-demethoxyacronycine, Chem. Pharm. Bull. 47 (1999)
1604e1606.
[8] A. Elomri, S. Mitaku, S. Michel, A.-L. Skaltsounis, F. Tillequin, M. Koch, A. Pierré,
N. Guilbaud, S. Léonce, L. Kraus-Berthier, Y. Rolland, G. Atassi, Synthesis and
cytotoxic and antitumor activity of esters in the 1,2-dihydroxy-1,2-dihy-
droacronycine series, J. Med. Chem. 39 (1996) 4762e4766.
[9] P. Magiatis, S. Mitaku, A.-L. Skaltsounis, F. Tillequin, M. Koch, A. Pierré,
Gh. Atassi, Synthesis and biological activity of esters in the trans-1,2-dihy-
droxy-1,2-dihydroacronycine series, J. Nat. Prod. 61 (1998) 198e201.
[10] T.M. Nguyen, C. Sittisombut, S. Boutefnouchet, M.-C. Lallemand, S. Michel,
M. Koch, F. Tillequin, R. Mazinghien, A. Lansiaux, M.-H. David-Cordonnier,
B. Pfeiffer, L. Kraus-Berthier, S. Léonce, A. Pierré, Synthesis, antitumor activity,
and mechanism of action of benzo[a]pyrano[3,2-h]acridin-7-one analogues of
acronycine, J. Med. Chem. 49 (2006) 3383e3394.
[11] N. Costes, H. Le Deit, S. Michel, F. Tillequin, M. Koch, B. Pfeiffer, P. Renard,
S. Léonce, N. Guilbaud, L. Kraus-Berthier, A. Pierré, G. Atassi, Synthesis and
cytotoxic and antitumor activity of benzo[b]pyrano[3,2-h]acridin-7-one
analogues of acronycine, J. Med. Chem. 43 (2000) 2395e2402.
[12] J.-B. Bongui, A. Elomri, D. Cahard, F. Tillequin, B. Pfeiffer, A. Pierré, E. Seguin,
Synthesis and cytotoxic activity of acronycine analogues in the benzo[c]pyr-
ano[3,2-h]acridin-7-one and naphtho[1,2-b][1,7] and [1,10]-phenanthrolin-7
(14H)-one series, Chem. Pharm. Bull. 53 (2005) 1540e1546.
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F. Tillequin, Acronycine derivatives: a promising series of anticancer agents,
Anti-Cancer Agents Med. Chem. 9 (2009) 804e815.
(log e): 207 (4.66), 249 (4.45), 294 (4.73), 377 (3.73), 393 (3.77). MS
(ESIþ) m/z: 510 and 512 [M þ H]þ, 532 and 534 [M þ Na]þ.
4.1.21. (ꢀ)-cis-10-Bromo-1,2-di-O-carbonyl-1,2-dihydroxy-6-
methoxy-3,3,14-trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano
[3,2-h]acridin-7-one (42)
N,N0-Carbonydiimidazole (54 mg, 333
mmol) was added to
a solution of (ꢀ)-cis-10-bromo-1,2-dihydroxy-6-methoxy-3,3,14-
trimethyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2-h]acridin-7-
one (38) (30.0 mg, 62.0 mmol) in 2-butanone (2 mL). The reaction
mixture was heated for 22 h at 75 ꢁC, and water (5 mL) was added.
An extractionwith dichloromethane (3 ꢃ10 mL) was performed and
the combined organic layers were dried over MgSO4, filtered and
evaporated under reduced pressure. Column chromatography on
silica gel (CH2Cl2/MeOH: 100/0 to 99.3/0.7: V/V) gave (ꢀ)-cis-
10-bromo-1,2-di-O-carbonyl-1,2-dihydroxy-6-methoxy-3,3,14-tri-
methyl-1,2,3,14-tetrahydro-7H-benzo[b]pyrano[3,2-h]acridin-7-
one (42) as a yellow amorphous solid. 1H NMR (CDCl3 þ CD3OD)
d:
1.43 (s, 3H, C-3MeA), 1.60 (s, 3H, C-3MeB), 3.94 (s, 3H, NMe), 3.95 (s,
3H, OMe), 4.85 (d, 1H, J ¼ 10 Hz, H-2), 6.28 (s, 1H, H-5), 6.33 (d, 1H,
J ¼ 10 Hz, H-1), 7.57 (dd, 1H, J ¼ 9 and 2 Hz, H-11), 7.65 (s, 1H, H-13),
7.73 (d,1H, J ¼ 9 Hz, H-12), 8.13 (d,1H, J ¼ 2 Hz, H-9), 8.68 (s,1H, H-8).
[14] H.D.T. Mai, T. Gaslonde, S. Michel, F. Tillequin, M. Koch, J.-B. Bongui, A. Elomri,
E. Seguin, B. Pfeiffer, P. Renard, M.-H. David-Cordonnier, W. Laine, C. Bailly,
L. Kraus-Berthier, S. Léonce, J.A. Hickman, A. Pierré, Structureeactivity rela-
tionships and mechanism of action of antitumor benzo[b]pyrano[3,2-h]acri-
din-7-one acronycine analogues, J. Med. Chem. 46 (2003) 3072e3082.
[15] M.-H. David-Cordonnier, W. Laine, A. Lansiaux, M. Kouach, G. Briand, A. Pierré,
J.A. Hickman, C. Bailly, Alkylation of Guanine in DNA by S23906-1, a novel
potent antitumor compound derived from the plant alkaloid acronycine,
Biochemistry 41 (2002) 9911e9920.
[16] M.-H. David-Cordonnier, W. Laine, A. Lansiaux, F. Rosu, P. Colson, E. de
Pauw, S. Michel, F. Tillequin, M. Koch, J. Hickman, A. Pierré, C. Bailly,
Covalent binding of antitumor benzoacronycines to double-stranded DNA
induces helix opening and the formation of single-stranded DNA: unique
13C NMR (CDCl3 þ CD3OD)
d: 21.8 (C-3MeA), 24.5 (C-3MeB), 44.3
(NMe), 56.5 (OMe), 71.1 (C-1), 74.4 (C-3), 79.0 (C-2), 95.5 (C-5), 97.6
(C-14b), 111.5 (C-6a), 113.2 (C-13), 118.6 (C-10), 126.6 (C-7a), 126.9
(C-8), 128.7 (C-12), 129.8 (C-8a), 131.2 (C-9), 132.0 (C-11), 134.3 (C-
12a), 142.5 (C-13a), 150.2 (C-14a), 153.8 (OCOO), 160.1 (C-4a), 163.8
(C-6), 178.8 (C]O). IR (KBr) cmꢂ1: 2984, 2953, 2921, 2848, 1793,
1641, 1618, 1587, 1497, 1396, 1203, 1178, 1097, 1088, 1026. UV lmax
(MeOH) nm (log e
): 209 (4.46), 291 (4.73), 437 (3.61). MS (ESIþ) m/z:
510 and 512 [M þ H]þ, 532 and 534 [M þ Na]þ, 548 and 550 [M þ K]þ.
consequences of
a novel DNA-bonding mechanism, Mol. Cancer Ther. 4
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4.2. Pharmacology
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Cell culture and cytotoxicity. L1210 and KB-3-1 cells were culti-
vated in RPMI 1640 or DMEM medium, respectively (Gibco) sup-
plemented with 10% fetal calf serum, 2 mM
L-glutamine, 100 units/
mL penicillin, 100 g/mL streptomycin, and 10 mM HEPES buffer
m
(pH 7.4). Cytotoxicity was measured by the microculture tetrazo-
lium assay (MTA) as described [25,26]. Cells were exposed to
graded concentrations of drug (nine serial dilutions in triplicate) for
four doubling times (48 h for L1210 cells and 96 h for KB-3-1 cells).
Results are expressed as IC50, the concentration that reduced by
50% the optical density of treated cells with respect to the optical
density of untreated controls.
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A biomimetic
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[22] Nguyên Hóan, Dérivés du bromo-6-méthoxy-2-naphtaldéhyde-1 d’intérêt
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Appendix. Supporting information
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of iodobenzamide analogues: potential D-2 dopamine receptor imaging
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Supplementary data related to this article can be found online at
doi:10.1016/j.ejmech.2011.02.050.
[25] S. Léonce, A. Pierré, M. Anstett, V. Perez, A. Genton, J.P. Bizzari, Gh. Atassi,
Effects of a new triazinoaminopiperidine derivative on adriamycin accumu-
lation and retention in cells displaying P-glycoprotein-mediated multidrug
resistance, Bio-Chem. Pharmacol. 44 (1992) 1707e1715.
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A. Dhainaut, M. Berlion, J.P. Bizarri, Gh. Atassi, In vitro and in vivo circumvention
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