Design, synthesis, and antiproliferative activity of some new pyrazole-fused amino derivatives of the pyranoxanthenone, pyranothioxanthenone, and pyranoacridone ring systems: A new class of cytotoxic agents

Article abstract of DOI:10.1021/jm011117g

A series of novel pyranoxanthenones, pyranothioxanthenones, and pyranoacridones have been designed and synthesized as analogues of the acridone alkaloid acronycine, and their DNA binding and in vitro cytotoxicities have been investigated. The title compounds were derived by reaction of the corresponding 6-tosylates 5a-e with 2-hydroxyethylhydrazine, followed by conversion of the free hydroxyl of the substituted ethanols 6a-e to the corresponding mesylates, which were then treated with the suitably substituted secondary amines to provide the target derivatives 8-27. An alternative synthetic procedure for the preparation of these types of compounds is also developed, which resulted in an improvement of the overall yield. The new compounds exhibited interesting cytotoxic activity against the murine leukemia L1210 cell line, being more active than the parent compound, and a number of them possessed cytotoxicity against some human solid tumor cell lines. Especially in the case of a colon adenocarcinoma cell line, their IC₅₀ values were comparable to that of mitoxantrone. The results of this study indicate that the incorporation of an amino-substituted pyrazole ring into the acronycine chromophore, or into its isosteres, results in an improvement of the lead compound's activity, and therefore, it may be of use in the search of new anticancer agents derived from this natural product.

Full text of DOI:10.1021/jm011117g

J . Med. Chem. 2002, 45, 2599-2609
2599
Design , Syn th esis, a n d An tip r olifer a tive Activity of Som e New P yr a zole-F u sed
Am in o Der iva tives of th e P yr a n oxa n th en on e, P yr a n oth ioxa n th en on e, a n d
P yr a n oa cr id on e Rin g System s: A New Cla ss of Cytotoxic Agen ts
Ioannis K. Kostakis,† Prokopios Magiatis,‡ Nicole Pouli,† Panagiotis Marakos,*,† Alexios-Leandros Skaltsounis,‡
Harris Pratsinis,§ Stephane Le´once,| and Alain Pierre´|
Divisions of Pharmaceutical Chemistry and Pharmacognosy, Department of Pharmacy, University of Athens,
Panepistimiopolis-Zografou, Athens 15771, Greece, Laboratory of Cell Proliferation & Aging, Institute of Biology,
NCSR “Democritos”, Athens 15310, Greece, and Institut de Recherches Servier, 11 Rue des Moulineaux,
92150 Suresnes, France
Received December 5, 2001
A series of novel pyranoxanthenones, pyranothioxanthenones, and pyranoacridones have been
designed and synthesized as analogues of the acridone alkaloid acronycine, and their DNA
binding and in vitro cytotoxicities have been investigated. The title compounds were derived
by reaction of the corresponding 6-tosylates 5a -e with 2-hydroxyethylhydrazine, followed by
conversion of the free hydroxyl of the substituted ethanols 6a -e to the corresponding mesylates,
which were then treated with the suitably substituted secondary amines to provide the target
derivatives 8-27. An alternative synthetic procedure for the preparation of these types of
compounds is also developed, which resulted in an improvement of the overall yield. The new
compounds exhibited interesting cytotoxic activity against the murine leukemia L1210 cell
line, being more active than the parent compound, and a number of them possessed cytotoxicity
against some human solid tumor cell lines. Especially in the case of a colon adenocarcinoma
cell line, their IC50 values were comparable to that of mitoxantrone. The results of this study
indicate that the incorporation of an amino-substituted pyrazole ring into the acronycine
chromophore, or into its isosteres, results in an improvement of the lead compound’s activity,
and therefore, it may be of use in the search of new anticancer agents derived from this natural
product.
In tr od u ction
The acridone alkaloid acronycine (1; Figure 1) has
attracted much attention over the last few years, due
to its broad spectrum of activity in experimental tumors,
including X-5563 myeloma, S-91 melanoma, and the
Ridgeway osteogenic sarcoma.1 However, the clinical
development of this agent was not successful, because
of its extremely low water solubility.2 Several structural
modifications of acronycine have been reported focusing
on substitutions on the acridone chromophore and the
pyran moiety as well.3 A certain number of these
derivatives exhibited promising antitumor properties,
with a wide spectrum of activity and an increased
potency on several tumor strains in vitro and in vivo.4
Furthermore, some pyranoxanthenones and pyran-
othioxanthenones (2a ,b; Figure 1), which can be viewed
as acronycine isosteres, have also demonstrated cyto-
toxicity comparable, or superior in some cases, to that
of the parent compound.5
On the other hand, the anthracene-9,10-dione mitox-
antrone (3; Figure 1) is an important anticancer agent
in clinical use today, and it has gained a well-estab-
F igu r e 1. Structures of acronycine, mitoxantrone, pyranox-
anthenones, and pyranothioxanthenones.
lished role in the treatment of human leukemia and
lymphomas, as well as in combination therapy of
advanced breast and ovarian cancers.6 Molecular mod-
eling and molecular pharmacology studies of mitox-
* To whom correspondence should be addressed. Phone: 30-1-
antrone and several structurally related compounds
revealed that the mode of action of this drug is multi-
modal in nature, though it is considered to be an
intercalating agent that exerts its action primarily
7274830. Fax: 30-1-7274747. E-mail: marakos@pharm.uoa.gr.
† Division of Pharmaceutical Chemistry, University of Athens.
‡ Division of Pharmacognosy, University of Athens.
§ NCSR “Democritos”.
| Institut de Recherches Servier.
10.1021/jm011117g CCC: $22.00 © 2002 American Chemical Society
Published on Web 05/10/2002

2600 J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12
Kostakis et al.
Sch em e 1a
a
Reagents: (a) p-toluenesulfonyl chloride, Na2CO3, Me2CO, reflux; (b) 2-hydroxyethylhydrazine, DMSO, 150 °C; (c) methanesulfonyl
chloride, Et3N, CH2Cl2, rt; (d) N,N-dialkylaminoethylamine, EtOH, reflux.
Sch em e 2a
through binding and interaction with DNA.7 A great
deal of research effort has been directed toward the
finding of some new derivatives that might retain the
remarkable anticancer activity of this agent, while
reducing or eliminating its side effects, mainly car-
diotoxicity and the development of resistant tumors
(MDR phenotype).8 The intensive search for active
compounds led to the in corporation of a pyrazole ring
fusion at the 1- and 9-positions of the tricyclic skeleton
of mitoxantrone. The resulting anthrapyrazoles are
endowed with the goals of significantly increasing the
spectrum of antitumor activity (including solid tumors)
while reducing the cardiotoxicity exhibited by the
quinone chemotypes.9 The remaining carbonyl has been
replaced by sulfur or nitrogen, and some highly active
molecules have also resulted.10
a
Reagents: (a) 1,3,5-trihydroxybenzene, ZnCl2, 1-butanol, 120
We have recently reported on the synthesis of a
°C; (b) 3-methyl-2-butenal, pyridine, 115 °C; (c) dimethyl sulfate,
number of amino-substituted pyranoxanthenones and
pyranothioxanthenones (2c,d ; Figure 1) which exhibited
potent cytotoxicity against the leukemia L1210 cell line,
when compared to acronycine.11 As a continuation of
this study, we present here the synthesis and biological
evaluation of a new class of compounds bearing struc-
tural similarity to both acronycine and the anthrapy-
razoles.
The objective of this investigation was to incorporate
a pyrazole ring fusion into the acridone and (thio)-
xanthenone ring of the acronycine analogues to study
the effect of this structural modification, commonly used
in similar antitumor series, on the cytotoxic activity of
the new compounds against leukemia and some solid
tumors in particular.
K2CO3, Me2CO, rt.
noracronycine (30) by treatment with 3-methyl-2-
butenal. The 9-hydroxyl of 30 was methylated with
dimethyl sulfate in the presence of potassium carbonate
to provide 4e.
The derivatives 4a -e were easily converted to the
corresponding tosylates 5a -e via standard conditions.
Treatment of the latter analogues with commercially
available 2-hydroxyethylhydrazine afforded the carbinols
6a -e. The structural assignment for the carbinols was
confirmed using NOESY experiments. The side chain
methylene, which is adjacent to the pyrazole ring,
possessed NOEs with the 5-aromatic proton, but not
with the 8-aromatic proton. Furthermore, the structure
of the above-mentioned carbinols was also confirmed by
Ch em istr y
a gradient inverse-detected long-range H-15N correla-
1
tion experiment at natural abundance, where a clear
cross-peak was observed between N-6 and both the
adjacent side chain methylene and the aromatic H-5.
The target compounds 8-27 were then prepared in
reasonable yields by the conversion of the carbinols
6a -e to the corresponding mesylates 7a -e followed by
nucleophilic substitution of the readily displaced mesyl
group of these compounds with the appropriately sub-
stituted secondary amines.
The synthesis of the target compounds is outlined in
Scheme 1. We used the 6-hydroxypyranoxanthenones
4a and 4b, 5a the 6-hydroxypyranothioxanthenone 4c,5c
and the 6-hydroxypyranoacridones 4d 12 and 4e as
starting materials. The synthesis of 4e has not previ-
ously been reported. Thus, as depicted in Scheme 2,
5-hydroxyanthranilic acid (28) was first reacted with
1,3,5-trihydroxybenzene to provide 1,3,7-trihydroxyac-
ridone (29), which was then converted to 9-hydroxybis-

Xanthenone, Thioxanthenone, and Acridone Derivatives
J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12 2601
Sch em e 3a
a
Reagents: (a) (i) (for 32a ) Ac2O, Et3N, CH2Cl2, rt, (ii) (for 32b) benzyl chloride, Na2CO3, NaI, Me2CO, reflux; (b) p-toluenesulfonyl
chloride, Na2CO3, Me2CO, reflux; (c) 2-hydroxyethylhydrazine, DMSO, 150 °C; (d) BCl3, CH2Cl2, 0 °C; (e) methanesulfonyl chloride, Et3N,
CH2Cl2, rt, (f) phenylboronic acid, 3-methyl-2-butenal, AcOH (glacial), toluene, reflux.
We have also attempted to prepare the amines 8-27
upon treatment of the tosylates 5a -e with the corre-
sponding 2-dialkylaminoethylhydrazines. However, none
of the desired products were obtained following this
procedure, possibly due to the instability of the substi-
tuted hydrazines to the high temperature and the
prolonged reaction time required.
An alternative methodology for the preparation of the
target amines was also developed which involves the
initial formation of the pyrazole ring followed by the
formation of the pyran ring. The synthetic pathway used
is depicted in Scheme 3 concerning the thioxanthenone
derivatives.
ronic acid and acetic acid to give the mesylate 7c, which
led to the desired amines 16-19 through nucleophilic
displacement of the mesylate with the required amine,
as described above. This reaction sequence resulted in
a marked improvement in the overall yield (approxi-
mately by 20%) taking into account the experimental
procedures toward the preparation of the pyran deriva-
tives 4a -e, while the use of some toxic reagents (N,N-
diethylaniline, necessary in the first procedure) and
extreme experimental conditions (e.g., high reaction
temperatures) were avoided. On the other hand, it
possesses the disadvantage of the use of certain expen-
sive reagents (e.g., 3-methyl-2-butenal).
The 3-acetate 32a was first prepared from 1,3-
dihydroxythioxanthen-9-one (31)5c and subsequently
converted to the corresponding tosylate 33a . Reaction
of 33a with 2-hydrohyethylhydrazine furnished com-
pound 34a through deprotection of the 3-hydroxyl,
instead of the anticipated formation of compound 34b.
Consequently, the less labile 3-benzyl ether 32b was
prepared upon reaction of 31 with benzyl bromide,
which, after prior conversion to the tosylate 33b,
provided the derivative 35 at reflux treatment with
2-hydrohyethylhydrazine. Removal of the benzyl group
was effectively accomplished by treatment of 35 with 1
M BCl3 in dichloromethane, since catalytic hydrogena-
tion was proved unsuccessful. Initial attempts at forma-
tion of the pyran ring through the reaction of the derived
phenol 34b with 3-chloro-3-methyl-1-butyne in the
presence of potassium carbonate, sodium iodide, and a
catalytic amount of copper iodide resulted in a complex,
unseparable mixture of products. We therefore first
prepared the mesylate 36a , which was then treated with
1 M BCl3 in dichloromethane at 0 °C to provide the
4-hydroxy derivative 36b. This was smoothly reacted
with 3-methyl-2-butenal in the presence of phenylbo-
To examine the DNA-binding properties and the in
vitro antineoplastic activity of these agents, the free
base forms of the amines 8-27 were converted into their
water-soluble hydrochloride or fumarate addition salts,
by treatment with either hydrochloric or fumaric acid,
respectively, in methanol.
Resu lts a n d Discu ssion
The new compounds were evaluated for their DNA-
binding affinity and for their in vitro cytotoxic activity
in the established model of the murine leukemia cell
line L1210, as well as against several human solid
tumor cell lines (colon HT-29, HCT 116, and HRT-18,
lung A549, and breast MDA-MB-231).
For comparative reasons, the hydroxyethyl and me-
syloxyethyl analogues 6a -e and 7a -e were also in-
cluded in the above-mentioned assays. The results,
comprising also the three reference compounds (acro-
nycine, mitoxantrone, and ellipticine), are presented in
Tables 1 and 2.
In general, the tested compounds proved to possess
weak ethidium bromide displacement potency. Some of

2602 J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12
Ta ble 1. Ethidium Bromide Displacement Assay
Kostakis et al.
Ta ble 2. Inhibition of Proliferation (IC50 Values in µMa)
human
breast
murine human
human human human
colon colon
HT-29 HCT-116 HRT-18
leukemia
L1210
lung
MDA-MB- colon
compd
6a
6b
6c
6d
6e
7a
7b
A549
231
>10
.10
>10
>100
100
>100
d
>100
50 (7)
53 (5)
d
12 (2)
>100
18 (5)
28 (12) 4 (0.5)
64 (18) >100
37 (10) 33 (12)
>100
d
8.7 (1.1) >100
3 (0.4) 90 (10)
31.9 (7.6) >100
26.7 (3.7) d
40 (15) 52 (12) 52 (17)
EC50
40 (7)
24 (2)
d
60 (19)
33 (8)
d
d
compd
X
R1
R2
R3
(µM)a
22 (8)
d
6a
6b
6c
6d
6e
7a
7b
7c
O
O
S
NCH3
NCH3
O
O
S
NCH3
NCH3
O
O
O
O
O
O
O
O
S
H
OCH3
H
H
H
H
OCH3
H
H
H
H
H
H
H
OCH3
OCH3
OCH3
OCH3
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
OH
OH
OH
OH
d
273.8
d
d
d
7c
7d
15 (1.5)
2.5 (0.25) d
d
>100
d
45 (25) 44 (12) 30 (8)
20 (5)
18 (6)
18 (8)
49 (12)
12 (7)
54 (23) 50 (17)
d
d
7e
0.4 (0.13) >100
9.8 (1.2) 32 (19)
9.1 (0.7) 10 (3)
8.3 (1.3) 27 (18)
10.1 (0.9) 15 (6)
14.6 (2.1) 50 (22)
9.9 (0.4) 33 (12)
10.6 (1.3) 33 (8)
16.5 (2) 31 (9)
12 (0.8)
50 (10)
9 (0.5)
12 (1)
20 (3)
48 (6)
11 (2.5)
11 (4)
37 (7)
8 (1)
28 (4)
9 (0.7)
21 (3)
12 (2)
15 (1.3)
8b
OCH3 OH
9b
9 (0.5) 40 (12) 5 (0.2)
H
H
H
H
OSO2CH3
OSO2CH3
OSO2CH3
OSO2CH3
d
d
10b
11c
12b
13b
14b
15c
16b
17b
18b
19b
20b
21b
22b
23b
24b
25b
26b
27b
9 (0.2) 42 (5)
6.5 (0.4) 20 (6)
30 (11)
10 (2)
>500
9 (0.3) 51 (18) 17 (2.5)
9 (0.2) 41 (4) 30 (14)
8 (0.9) 43 (11) 60 (18)
6 (1.1) 54 (17) 12 (2)
7.5 (0.5) 50 (15) 10 (0.7)
7d
d
d
7e
OCH3 OSO2CH3
8b
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
H
N(CH3)2
N(CH2CH3)2
N(CH2)4
N(CH2)5
N(CH3)2
N(CH2CH3)2
N(CH2)4
N(CH2)5
N(CH3)2
N(CH2CH3)2
N(CH2)4
N(CH2)5
N(CH3)2
N(CH2CH3)2
N(CH2)4
N(CH2)5
431.1
d
d
9b
37 (12)
20 (13)
10b
11c
12b
13b
14b
15c
16b
17b
18b
19b
20b
21b
22b
23b
24b
25b
26b
27b
10.1 (1.4) 26 (11)
6.5 (0.2) 8 (0.5)
17.2 (4.2) 30 (5)
6.9 (0.8) 10 (2)
4.7 (0.5) 19 (7)
7.5 (0.5) 10 (1.5) 10 (0.5)
6.7 (0.3) 29 (3.1) 11 (0.9)
5.9 (0.1) 41 (9)
17 (3)
9 (1)
33 (6)
30 (7)
40 (15)
12 (0.8)
d
10 (1.5) 61 (22) 30 (5)
149.5
273.2
71.7
289.9
>500
282.3
257.0
334.2
211.8
d
3.1 (0.9) 10 (2)
6 (0.8) 17 (4)
3 (0.4) 11 (2)
5 (1.3) 21 (6)
9 (0.6) 30 (16)
12 (3)
18 (10)
24 (12)
43 (13)
d
10 (1)
S
S
S
2 (0.2) 10 (0.2) 10 (0.8)
3.1 (0.1) 8.5 (1.5) >100
2.7 (0.3) 10 (0.7) 50 (11)
4 (2)
8 (0.5)
d
5.5 (2.5) 7 (0.4)
20 (7)
6.5 (2.5) 11 (1.5) 40 (12)
NCH3
NCH3
NCH3
NCH3
NCH3
NCH3
NCH3
NCH3
acrony-
27 (4.1) >100
d
>100
>100
>100
cine
204.9
175.8
>500
d
mitox-
d
d
0.3 (0.05) 1 (0.08)
8 (3.9)
d
d
d
d
antrone
OCH3 N(CH3)2
OCH3 N(CH2CH3)2
OCH3 N(CH2)4
OCH3 N(CH2)5
ellipticine
10 (0.2) 2.3 (0.2) 15 (5)
a
The results represent the mean (( standard deviation) of three
independent experiments and are expressed as IC50, the concen-
tration that reduced by 50% the optical density of treated cells
d
H
390.6
270.4
3.4
acronycine
mitoxantrone
ellipticine
with respect to untreated controls. Fumarate. c Hydrochloride.
b
d
Not tested.
22.2
a
The results represent the mean of two individual experiments
((1-10%) and are expressed as EC50, the concentration of the
compound that causes a 50% reduction in the fluorescence of the
values below or around 10 µM for the whole spectrum
of cell lines used. In conclusion, through the structural
modifications of acronycine presented here, we have
achieved significant enhancement of the activity of the
new compounds against the leukemia cells, concurrently
extending their effectiveness against solid tumor cells.
b
calf thymus DNA/ethidium bromide complex. Fumarate. c Hy-
d
drochloride. Not tested.
them were more potent than acronycine (14 > 12 > 23
> 22 > 20 > 18 > acronycine), but the most potent, 14,
was clearly 1 order of magnitude weaker than mitox-
antrone. However, their cytotoxic activity was undoubt-
edly more promising. In particular, a certain number
of the derivatives 6 and 7 showed strong cytotoxicity
against the L1210 leukemia cell line. More precisely,
the hydroxyethylacridine analogues 6d and 6e are,
respectively, 3- and 9-fold more active than acronycine,
whereas the corresponding mesylates 7d and 7e proved
to be even more active, being, respectively, 10- and 65-
fold more potent than the reference compound. Fur-
thermore, all the evaluated amines 8-27 (with the
exception of 16) were more potent than acronycine
against leukemia L1210 cells. The activity of these
compounds was also extended against the solid tumor
cell lines. Especially against colon HT-29 cells, the
compounds 22, 20, 25, 23, 26, 15, 11, and 27 were more
active than the reference compound mitoxantrone. The
other solid tumor cell lines were in general less sensitive
to the above-mentioned compounds than to mitox-
antrone. Nevertheless, some of the new derivatives such
as 25, 20, and 22 exhibited a universal profile of IC50
Exp er im en ta l Section
All chemicals were purchased from Aldrich Chemical Co.
Melting points were determined on a Bu¨chi apparatus and are
1
uncorrected. H NMR spectra and 2D spectra were recorded
on a Bruker Avanche 400 instrument, whereas 13C NMR
spectra were recorded on a Bruker AC 200 spectrometer in
deuterated solvents and were referenced to TMS (δ scale). The
1
signals of H and 13C spectra were unambiguously assigned
by using 2D NMR techniques: 1H-1H COSY, NOESY, HMQC,
and HMBC. For the 1H-15N GHMQC spectrum, data were
acquired as 3072 × 400 data points with a total of 290
transients accumulated per t1 increment. Pulse widths were
8.55 µs for 1H and 27.7 µs for the 15N at powers of 0 dB and
-3 dB. The F1 spectral window employed was set from 100 to
400 ppm. Pulsed field gradients, gt1-gt3, had durations of 0.8
ms. Gradient pairs were optimized as 70/30/50 for 15N. Flash
chromatography was performed on Merck silica gel 60 (0.040-
0.063 mm). Analytical thin-layer chromatography (TLC) was
carried out on precoated (0.25 mm) Merck silica gel F-254
plates. Elemental analyses were performed at the Microana-
lytical Sections of the National Hellenic Research Foundation
on a Perkin-Elmer PE 240C elemental analyzer (Norwalk, CT)
and are within (0.4% of the theoretical values.

Xanthenone, Thioxanthenone, and Acridone Derivatives
J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12 2603
1,3,7-Tr ih yd r oxya cr id on e (29). To a solution of 5-hy-
droxyanthranilic acid (28) (12.1 g, 78.9 mmol) in 1-butanol (50
mL) were added phloroglucinol (10.9 g, 78.9 mmol) and ZnCl2
(10.8 g, 78.9 mmol). The reaction mixture was stirred for 5 h
at 120 °C, and the water produced was removed with a Dean-
Stark apparatus. The resulting precipitate was filtered and
washed with water and CH2Cl2 to give 29 (9.20 g, 48%): mp
280-282 °C dec (EtOH); 1H NMR (DMSO-d6, 200 MHz) δ 5.95
(d, J ) 1 Hz, 1H, H-2), 6.21 (d, J ) 1 Hz, 1H, H-4), 7.23 (dd,
J ) 9, 2.5 Hz, 1H, H-6), 7.36 (d, J ) 9 Hz, 1H, H-5), 7.44 (d,
J ) 2.5 Hz, 1H, H-8), 9.75 (br s, 1H, D2O exch, NH), 10.50 (br
s, 1H, D2O exch, OH-7), 11.66 (s, 1H, D2O exch, OH-3), 14.34
(s, 1H, D2O exch, OH-1). Anal. (C13H9NO4) C, H, N.
7,12-Dih yd r o-6,9-d ih yd r oxy-3,3-d im et h yl-3H -p yr a n o-
[2,3-c]a cr id in -7-on e (30). To a solution of 29 (200 mg, 0.82
mmol) in dry pyridine (1 mL) was added 3-methyl-2-butenal
(0.2 mL, 2.1 mmol), and the reaction mixture was stirred for
1.5 h at 115 °C. Then the reagents were removed under
reduced pressure (using a high-vacuum pump), and the solid
residue was submitted to flash chromatography with cyclo-
hexane/EtOAc (80/20 to 50/50) to give compound 30 (101 mg,
40%): mp > 280 °C dec (EtOH); 1H NMR (DMSO-d6, 400 MHz)
δ 1.41 (s, 6H, 2 gem-CH3), 5.67 (d, J ) 10 Hz, 1H, H-2), 5.99
(s, 1H, H-5), 7.05 (d, J ) 10 Hz, 1H, H-1), 7.30 (dd, J ) 9, 3
Hz, 1H, H-10), 7.48 (d, J ) 3 Hz, 1H, H-8), 7.69 (d, J ) 9 Hz,
1H, H-11), 9.75 (s, 1H, D2O exch, 9-OH), 11.08 (s, 1H, D2O
exch, NH), 14.83 (s, 1H, D2O exch, 6-OH); 13C NMR (DMSO,
50 MHz) δ 27.48 (2 CH3), 76.96 (C-3), 95.74 (C-5), 97.65 (C-
12b), 103.60 (C-6a), 106.91 (C-8), 116.25 (C-1), 119.23 (C-11),
119.92 (C-7a), 124.63 (C-10), 125.32 (C-2), 134.70 (C-11a),
137.49 (C-12a), 152.56 (C-9), 158.77 (C-4a), 163.77 (C-6), 179.87
(C-7). Anal. (C18H15NO4) C, H, N.
7,12-Dih yd r o-6-h yd r oxy-9-m et h oxy-3,3,12-t r im et h yl-
3H-p yr a n o[2,3-c]a cr id in -7-on e (4e). To a solution of 30 (1.13
g, 3.65 mmol) in dry acetone (20 mL) were added dimethyl
sulfate (9.0 mL) and anhydrous K2CO3 (2.0 g). The reaction
mixture was stirred for 24 h at room temperature. The
resulting precipitate was filtered and washed with water to
give pure 4e (736 mg, 60%): mp 181-183 °C (EtOH); 1H NMR
(CDCl3, 400 MHz) δ 1.54 (s, 6H, 2 gem-CH3), 3.92 (s, 3H,
NCH3), 3.94 (s, 3H, 9-OCH3), 5.50 (d, J ) 10 Hz, 1H, H-2),
6.27 (s, 1H, H-5), 6.57 (d, J ) 10 Hz, 1H, H-1), 7.36 (dd, J )
9, 3 Hz, 1H, H-10), 7.41 (d, J ) 9 Hz, 1H, H-11), 7.77 (d, J )
3 Hz, 1H, H-8), 14.80 (s, 1H, D2O exch, 6-OH); 13C NMR
(CDCl3, 50 MHz) δ 26.79 (2 CH3), 43.66 (NCH3), 55.75 (OCH3),
76.90 (C-3), 97.54 (C-5), 100.56 (C-12b), 105.30 (C-8), 106.66
(C-6a), 117.79 (C-11), 121.58 (C-1), 122.50 (C-2, C-7a), 124.45
(C-10), 139.63 (C-11a), 144.11 (C-12a), 154.92 (C-9), 161.39 (C-
4a), 165.10 (C-6), 180.39 (C-7). Anal. (C20H19NO4) C, H, N.
3,3-Dim eth yl-6-[[(4-m eth ylp h en yl)su lfon yl]oxy])-3H,-
7H-p yr a n o[2,3-c]xa n th en -7-on e (5a ). To a solution of 3,3-
dimethyl-6-hydroxy-3H,7H-pyrano[2,3-c]xanthen-7-one (4a; 1.32
g, 4.5 mmol)5a in dry acetone (20 mL) were added under argon
p-toluenesulfonyl chloride (1.7 g, 9 mmol) and anhydrous
sodium carbonate (1.9 g, 18 mmol), and the mixture was
refluxed for 4 h. The mixture was then vacuum-evaporated
and extracted with CH2Cl2-water, the combined extracts were
dried (Na2SO4) and vacuum-evaporated, and the residue was
purified by column chromatography, using CH2Cl2 as the
eluent, to give compound 5a (1.79 g, 89%): mp 158-160 °C
(Et2O-n-hexane); 1H NMR (CDCl3, 400 MHz) δ 1.42 (s, 6H, 2
gem-CH3), 2.35 (s, 3H, 4′-CH3), 5.66 (d, J ) 10.5 Hz, 1H, H-2),
6.55 (s, 1H, H-5), 6.81 (d, J ) 10.5 Hz, 1H, H-1), 7.30 (d, J )
8 Hz, 2H, H-3′, H-5′), 7.46 (m, 3H, H-9, H-10, H-11), 7.91 (d,
J ) 8 Hz, 2H, H-2′, H-6′), 8.16 (dd, J ) 8, 2 Hz, 1H, H-8).
Anal. (C25H20O6S) C, H.
2H, H-3′, H-5′), 7.79 (dd, J ) 8, 1.2 Hz, 1H, H-8), 7.99 (d, J )
8 Hz, 2H, H-2′, H-6′). Anal. (C26H22O7S) C, H.
3,3-Dim eth yl-6-[[(4-m eth ylp h en yl)su lfon yl]oxy])-3H,-
7H-p yr a n o[2,3-c]th ioxa n th en -7-on e (5c). This compound
was prepared by a procedure analogous to that of 5a , starting
from 4c:5c yield 96%; mp 187-189 °C (Et2O); 1H NMR (CDCl3,
400 MHz) δ 1.45 (s, 6H, 2 gem-CH3), 2.30 (s, 3H, 4′-CH3), 5.78
(d, J ) 10 Hz, 1H, H-2), 6.74 (s, 1H, H-5), 6.61 (d, J ) 10 Hz,
1H, H-1), 7.31 (d, J ) 8 Hz, 2H, H-3′, H-5′), 7.49 (m, 3H, H-9,
H-10, H-11), 7.82 (d, J ) 8 Hz, 2H, H-2′, H-6′), 8.25 (dd, J )
8, 1 Hz, 1H, H-8). Anal. (C25H20O5S2) C, H.
3,3,12-Tr im et h yl-6-[[(4-m et h ylp h en yl)su lfon yl]oxy])-
3H,7H-p yr a n o[2,3-c]a cr id in -7-on e (5d ). This compound was
prepared by a procedure analogous to that of 5a , starting from
1
4d :12 yield 89%; mp 198-201 °C (Et2O-n-pentane); H NMR
(CDCl3, 400 MHz) δ 1.40 (s, 3H, gem-CH3), 1.49 (s, 3H, gem-
CH3), 2.39 (s, 3H, 4′-CH3), 3.78 (s, 3H, NCH3), 5.58 (d, J ) 10
Hz, 1H, H-2), 6.53 (d, J ) 10 Hz, 1H, H-1), 6.57 (s, 1H, H-5),
7.20 (t, J ) 8 Hz, 1H, H-9), 7.29 (d, J ) 8 Hz, 2H, H-3′, H-5′),
7.32 (d, J ) 8 Hz, 1H, H-11), 7.61 (td, J ) 8, 1.5 Hz, 1H, H-10),
7.97 (d, J ) 8 Hz, 2H, H-2′, H-6′), 8.27 (dd, J ) 8, 1.5 Hz, 1H,
H-8). Anal. (C26H23NO5S) C, H, N.
9-Meth oxy-3,3,12-tr im eth yl-6-[[(4-m eth ylp h en yl)su lfo-
n yl]oxy]-3H,7H-p yr a n o[2,3-c]a cr id in -7-on e (5e). This com-
pound was prepared by a procedure analogous to that of 5a ,
starting from 4e: yield 67%; mp 188-191 °C (Et2O-n-
pentane); 1H NMR (CDCl3, 400 MHz) δ 1.53 (s, 6H, 2 gem-
CH3), 2.45 (s, 3H, 4′-CH3), 3.82 (s, 3H, NCH3), 3.92 (s, 3H,
9-OCH3), 5.60 (d, J ) 10 Hz, 1H, H-2), 6.51 (s, 1H, H-5), 6.56
(d, J ) 10 Hz, 1H, H-1), 7.27 (dd, J ) 9, 3 Hz, 1H, H-10), 7.33
(d, J ) 9 Hz, 1H, H-11), 7.36 (d, J ) 8 Hz, 2H, H-3′, H-5′),
7.80 (d, J ) 3 Hz, 1H, H-8), 8.03 (d, J ) 8 Hz, 2H, H-2′, H-6′).
Anal. (C27H25NO6S) C, H, N.
2-[6,9-Dih yd r o-9,9-d im eth yl(1)ben zop yr a n o[4,3,2-c,d ]-
p yr a n o[3,2-f]in d a zol -6-yl]-1-eth a n ol (6a ). To a solution of
5a (1.93 g, 4.31 mmol) in dry DMSO (25 mL) was added
2-hydroxyethylhydrazine (1.5 mL, 22 mmol), and the mixture
was heated, under argon, at 150 °C for 90 min. Upon cooling,
the mixture was poured into water and extracted with CH2-
Cl2. The organic phase was dried over Na2SO4, and the solvent
was vacuum-evaporated. The residue was purified by column
chromatography, using a mixture of cyclohexane/EtOAc (60/
40 to 30/70) as the eluent, to give compound 6a (835 mg,
58%): mp 180-182 °C (EtOAc); 1H NMR (CDCl3, 400 MHz) δ
1.40 (s, 6H, 2 gem-CH3), 3.35 (t, J ) 4 Hz, 1H, D2O exch, OH),
4.08 (q, J ) 5, 4 Hz, 2H, NCH2CH2), 4.32 (t, J ) 5 Hz, 2H,
NCH2CH2), 5.61 (d, J ) 10 Hz, 1H, H-10), 6.21 (s, 1H, H-7),
6.69 (d, J ) 10 Hz, 1H, H-11), 7.21-7.35 (m, 3H, H-1, H-2,
H-3), 8.05 (dd, J ) 8, ∼0 Hz, 1H, H-4); 13C NMR (CDCl3, 50
MHz) δ 27.78 (2 gem-CH3), 51.05 (NCH2CH2), 62.01 (NCH2CH2),
76.83 (C-9), 88.84 (C-7), 100.39 (C-11a), 111.62 (C-11c), 115.52
(C-11), 118.07 (C-4a), 118.26 (C-1), 123.14 (C-4), 124.28 (C-3),
127.89 (C-10), 129.93 (C-2), 138.83 (C-4b), 140.31 (C-6a), 144.51
(C-7a), 154.74 (C-12a), 156.88 (C-11b). Anal. (C20H18N2O3) C,
H, N.
2-[6,9-Dih ydr o-9,9-dim eth yl-1-m eth oxy(1)ben zopyr an o-
[4,3,2-c,d ]p yr a n o[3,2-f]in d a zol-6-yl]-1-eth a n ol (6b). This
compound was prepared by a procedure analogous to that of
6a : yield 59%; mp 217-218 °C (EtOAc); 1H NMR (CDCl3, 400
MHz) δ 1.40 (s, 6H, 2 gem-CH3), 3.25 (t, J ) 5.5 Hz, 1H, D2O
exch, OH), 3.95 (s, 3H, OCH3), 4.13 (q, J ) 5.5, 5 Hz, 2H,
NCH2CH2), 4.32 (t, J ) 5 Hz, 2H, NCH2CH2), 5.65 (d, J ) 10
Hz, 1H, H-10), 6.28 (s, 1H, H-7), 6.80 (d, J ) 10 Hz, 1H, H-11),
6.95 (dd, J ) 8, 1.5 Hz, 1H, H-2), 7.12 (t, J ) 8 Hz, 1H, H-3),
7.47 (dd, J ) 8, 1.5 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz)
δ 27.58 (2 gem-CH3), 51.05 (NCH2CH2), 56.33 (OCH3), 62.01
(NCH2CH2), 76.73 (C-9), 89.13 (C-7), 100.65 (C-11a), 112.00
(C-11c), 112.88 (C-2), 114.99 (C-4), 115.88 (C-11), 118.99 (C-
4a), 123.99 (C-3), 127.79 (C-10), 139.02 (C-4b), 140.55 (C-6a),
144.14 (C-1), 144.19 (C-7a), 144.41 (C-12a), 156.81 (C-11b).
Anal. (C21H20N2O4) C, H, N.
3,3-Dim eth yl-11-m eth oxy-6-[[(4-m eth ylph en yl)su lfon yl]-
oxy]-3H,7H-p yr a n o[2,3-c]xa n th en -7-on e (5b). This com-
pound was prepared by a procedure analogous to that of 5a ,
starting from 4b:5a yield 91%; mp 154-156 °C (Et2O); 1H NMR
(CDCl3, 400 MHz) δ 1.52 (s, 6H, 2 gem-CH3), 2.43 (s, 3H, 4′-
CH3), 3.98 (s, 3H, OCH3), 5.72 (d, J ) 10 Hz, 1H, H-2), 6.68
(s, 1H, H-5), 6.97 (d, J ) 10 Hz, 1H, H-1), 7.16 (dd, J ) 8, 1.2
Hz, 1H, H-10), 7.24 (t, J ) 8 Hz, 1H, H-9), 7.33 (d, J ) 8 Hz,
2-[6,9-Dih yd r o-9,9-d im eth yl(1)ben zoth iop yr a n o[4,3,2-
c,d ]p yr a n o[3,2-f]in d a zol-6-yl]-1-eth a n ol (6c). This com-
pound was prepared by a procedure analogous to that of 6a :

2604 J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12
Kostakis et al.
yield 62%; mp 167-169 °C (EtOAc); 1H NMR (CDCl3, 400
MHz) δ 1.40 (s, 3H, gem-CH3), 1.51 (s, 3H, gem-CH3), 3.40 (t,
J ) 4.5 Hz, 1H, D2O exch, OH), 4.13 (q, J ) 5, 4.5 Hz, 2H,
NCH2CH2), 4.20 (t, J ) 5 Hz, 2H, NCH2CH2), 5.72 (d, J ) 10
Hz, 1H, H-10), 6.31 (s, 1H, H-7), 6.35 (d, J ) 10 Hz, 1H, H-11),
7.15-7.38 (m, 3H, H-1, H-2, H-3), 7.95 (dd, J ) 8, ∼0 Hz, 1H,
H-4); 13C NMR (CDCl3, 50 MHz) δ 27.78 (2 gem-CH3), 50.58
(NCH2CH2), 61.84 (NCH2CH2), 76.59 (C-9), 91.07 (C-7), 109.70
(C-11a), 115.82 (C-11c), 117.70 (C-11), 123.91 (C-4), 125.42 (C-
4a), 125.78 (C-11b), 126.58 (C-1), 126.80 (C-3), 128.45 (C-2),
129.25 (C-10), 133.20 (C-12a), 140.65 (C-6a), 141.81 (C-4b),
155.06 (C-7a). Anal. (C20H18N2O2S) C, H, N.
1H NMR (CDCl3, 400 MHz) δ 1.42 (s, 6H, 2 gem-CH3), 2.74 (s,
3H, SO2CH3), 3.95 (s, 3H, OCH3), 4.45 (t, J ) 5 Hz, 2H, NCH2-
CH2), 4.64 (t, J ) 5 Hz, 2H, NCH2CH2), 5.62 (d, J ) 10 Hz,
1H, H-10), 6.30 (s, 1H, H-7), 6.79 (d, J ) 10 Hz, 1H, H-11),
6.95 (dd, J ) 8, ∼0.5 Hz, 1H, H-2), 7.10 (t, J ) 8 Hz, 1H, H-3),
7.44 (dd, J ) 8, 0.5 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz)
δ 27.59 (2 gem-CH3), 37.27 (SO2CH3), 48.16 (NCH2CH2), 56.24
(OCH3), 67.73 (NCH2CH2), 76.83 (C-9), 89.06 (C-7), 100.84 (C-
11a), 111.76 (C-11c), 112.95 (C-2), 114.79 (C-4), 115.64 (C-11),
118.60 (C-4a), 124.01 (C-3), 127.96 (C-10), 139.34 (C-4b), 140.60
(C-6a), 144.05 (C-7a), 144.34 (C-12a), 149.14 (C-1), 157.05 (C-
11b). Anal. (C22H22N2O6S) C, H, N.
2-[6,9-Dih yd r o-9,9-d im eth yl(1)ben zoth iop yr a n o[4,3,2-
c,d]pyr an o[3,2-f]in dazol-6-yl]-1-eth an ol Meth an esu lfon ate
(7c).
Meth od A. This compound was prepared according to the
procedure reported for 7a : yield 95%.
2-[6,12-Dih yd r o-9,9,12-tr im eth yl-9H-p yr a n o[2,3-c]p yr a -
zolo[3,4,5-m ,n ]a cr id in -6-yl]-1-eth a n ol (6d ). This compound
was prepared by a procedure analogous to that of 6a : yield
73%; mp 223-225 °C (EtOAc-n-hexane); 1H NMR (CDCl3, 400
MHz) δ 1.47 (s, 6H, 2 gem-CH3), 3.10 (t, J ) 4 Hz, 1H, D2O
exch, OH), 3.72 (s, 3H, NCH3), 4.07 (q, J ) 4.5, 4 Hz, 2H,
NCH2CH2), 4.26 (t, J ) 4.5 Hz, 2H, NCH2CH2), 5.55 (d, J )
10 Hz, 1H, H-10), 6.17 (s, 1H, H-7), 6.72 (d, J ) 10 Hz, 1H,
H-11), 7.10 (t, J ) 8 Hz, 1H, H-3), 7.16 (d, J ) 8 Hz, 1H, H-1),
7.37 (td, J ) 8, 1.5 Hz, 1H, H-2), 7.91 (dd, J ) 8, 1.5 Hz, 1H,
H-4); 13C NMR (CDCl3, 50 MHz) δ 26.78 (2 gem-CH3), 40.57
(NCH3), 51.37 (NCH2CH2), 60.16 (NCH2CH2), 74.68 (C-9),
87.14 (C-7), 98.50 (C-11a), 113.35 (C-11c), 116.76 (C-1), 118.60
(C-4a), 120.89 (C-11), 121.91 (C-4, C-3), 124.74 (C-10), 129.33
(C-2), 136.06 (C-11b), 139.85 (C-4b), 140.33 (C-6a), 143.89 (C-
12a), 156.87 (C-7a). Anal. (C21H21N3O2) C, H, N.
Meth od B. A mixture of 36b (56 mg, 0.154 mmol), phenyl-
boronic acid (20 mg, 0.164 mmol), 3-methyl-2-butenal (14.7 µL,
0.152 mmol), and glacial acetic acid (3.9 mL) in toluene (30
mL) was heated under reflux for 2 h with azeotropic removal
of water using a Dean-Stark trap. After cooling, the reaction
mixture was concentrated and the residue was purified by
column chromatography, using a mixture of dichloromethane/
EtOAc (95/5) as the eluent, to give 7c (21.5 mg, 33%):
1
mp 153-155 °C (Et2O); H NMR (CDCl3, 400 MHz) δ 1.40
(s, 6H, 2 gem-CH3), 2.78 (s, 3H, SO2CH3), 4.41 (t, J ) 5 Hz,
2H, NCH2CH2), 4.62 (t, J ) 5 Hz, 2H, NCH2CH2), 5.67 (d, J )
10 Hz, 1H, H-10), 6.32 (d, J ) 10 Hz, 1H, H-11), 6.33 (s, 1H,
H-7), 7.18-7.30 (m, 3H, H-1, H-2, H-3), 7.98 (dd, J ) 8, ∼0
Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ 27.72 (2 gem-CH3),
37.30 (SO2CH3), 47.82 (NCH2CH2), 67.70 (NCH2CH2), 76.56
(C-9), 91.18 (C-7), 109.80 (C-11a), 115.67 (C-11c), 117.56 (C-
11), 123.82 (C-4), 125.15 (C-4a), 125.37 (C-11b), 126.60 (C-1),
126.78 (C-3), 128.51 (C-2), 129.40 (C-10), 133.19 (C-12a), 140.99
(C-6a), 142.23 (C-4b), 155.11 (C-7a). Anal. (C21H20N2O4S2) C,
H, N.
2-[6,12-Dih ydr o-3-m eth oxy-9,9,12-tr im eth yl-9H-pyr an o-
[2,3-c]pyr a zolo[3,4,5-m,n ]a cr idin -6-yl]-1-eth a n ol (6e). This
compound was prepared by a procedure analogous to that of
1
6a : yield 65%; mp 186-188 °C (EtOAc-n-hexane); H NMR
(CDCl3, 400 MHz) δ 1.49 (s, 6H, 2 gem-CH3), 2.95 (t, J ) 5.1
Hz, 1H, D2O exch, OH), 3.71 (s, 3H, NCH3), 3.90 (s, 3H,
9-OCH3), 4.09 (q, J ) 5.1, 4.5 Hz, 2H, NCH2CH2), 4.27 (t, J )
4.5 Hz, 2H, NCH2CH2), 5.55 (d, J ) 10 Hz, 1H, H-10), 6.15 (s,
1H, H-7), 6.72 (d, J ) 10 Hz, 1H, H-11), 6.97 (dd, J ) 9, 3 Hz,
1H, H-2), 7.11 (d, J ) 9 Hz, 1H, H-1), 7.40 (d, J ) 3 Hz, 1H,
H-4); 13C NMR (CDCl3, 50 MHz) δ 26.94 (2 gem-CH3), 40.83
(NCH3), 50.54 (NCH2CH2), 55.72 (OCH3), 62.08 (NCH2CH2),
75.09 (C-9), 85.78 (C-7), 98.72 (C-11a), 105.34 (C-4), 114.16
(C-11c), 117.13 (C-2), 117.39 (C-1), 119.34 (C-4a), 120.99 (C-
11), 124.41 (C-10), 135.00 (C-6a), 138.49 (C-11b), 140.73 (C-
12a),141.57 (C-4b),154.70 (C-3),157.97 (C-7a).Anal.(C22H23N3O3)
C, H, N.
2-[6,12-Dih yd r o-9,9,12-tr im eth yl-9H-p yr a n o[2,3-c]p yr a -
zolo[3,4,5-m ,n ]a cr id in -6-yl]-1-eth a n ol Meth a n esu lfon a te
(7d ). This compound was prepared by a procedure analogous
1
to that of 7a : yield 95%; mp 182-185 °C (EtOAc); H NMR
(CDCl3, 400 MHz) δ 1.45 (s, 6H, 2 gem-CH3), 3.66 (s, 3H,
NCH3), 3.74 (s, 3H, SO2CH3), 4.43 (t, J ) 4.5 Hz, 2H, NCH2-
CH2), 4.64 (t, J ) 4.5 Hz, 2H, NCH2CH2), 5.53 (d, J ) 10 Hz,
1H, H-10), 6.19 (s, 1H, H-7), 6.77 (d, J ) 10 Hz, 1H, H-11),
7.09 (t, J ) 8 Hz, 1H, H-3), 7.11 (d, J ) 8 Hz, 1H, H-1), 7.33
(td, J ) 8, 1.5 Hz, 1H, H-2), 7.88 (dd, J ) 8, 1.5 Hz, 1H, H-4);
13C NMR (CDCl3, 50 MHz) δ 26.86 (2 gem-CH3), 20.74 (SO2-
CH3), 40.72 (NCH3), 47.82 (NCH2CH2), 67.85 (NCH2CH2),
75.05 (C-9), 86.55 (C-7), 99.38 (C-11a), 113.79 (C-11c), 116.10
(C-1), 118.68 (C-4a), 120.77 (C-11), 121.91 (C-3), 122.61 (C-4),
125.04 (C-10), 129.41 (C-2), 136.54 (C-11b), 140.95 (C-6a),
141.94 (C-4b), 144.30 (C-12a), 157.97 (C-7a). Anal. (C22H23N3O4S)
C, H, N.
2-[6,9-Dih yd r o-9,9-d im eth yl(1)ben zop yr a n o[4,3,2-c,d ]-
p yr a n o[3,2-f]in d a zol-6-yl]-1-et h a n ol Met h a n esu lfon a t e
(7a ). Methanesulfonyl chloride (658 µL, 8.5 mmol) was added
to a stirred suspension of 6a (882 mg, 2.64 mmol) and
triethylamine (1.35 mL, 9.7 mmol) in dry dichloromethane (40
mL) with cooling to 0 °C. The cooling bath was removed, and
the mixture was stirred at room temperature for 4 h. The
reaction mixture was partitioned between dichloromethane
and 1 N sodium hydroxide, and the organic phase was washed
with HCl (10%), water, and brine, then dried (Na2SO4), and
concentrated to dryness. The residue was purified by flash
chromatography eluting with a 70/30 to 50/50 cyclohexane/
EtOAc mixture to afford compound 7a (1.02 g, 94%); mp 155-
157 °C (EtOAc-n-pentane); 1H NMR (CDCl3, 400 MHz) δ 1.42
(s, 6H, 2 gem-CH3), 2.76 (s, 3H, SO2CH3), 4.45 (t, J ) 5 Hz,
2H, NCH2CH2), 4.61 (t, J ) 5 Hz, 2H, NCH2CH2), 5.60 (d, J )
10 Hz, 1H, H-10), 6.28 (s, 1H, H-7), 6.66 (d, J ) 10 Hz, 1H,
H-11), 7.12-7.31 (m, 3H, H-1, H-2, H-3), 8.05 (dd, J ) 8, ∼0
Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ 27.64 (2 gem-CH3),
37.24 (SO2CH3), 48.13 (NCH2CH2), 67.68 (NCH2CH2), 76.76
(C-9), 88.98 (C-7), 100.53 (C-11a), 111.64 (C-11c), 115.33 (C-
11), 117.90 (C-4a), 118.26 (C-1), 122.97 (C-4), 124.23 (C-3),
128.04 (C-10), 130.00 (C-2), 139.24 (C-4b), 140.55 (C-6a), 144.47
(C-7a), 154.65 (C-12a), 156.93 (C-11b). Anal. (C21H20N2O5S) C,
H, N.
2-[6,12-Dih ydr o-3-m eth oxy-9,9,12-tr im eth yl-9H-pyr an o-
[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in -6-yl]-1-et h a n ol Met h -
a n esu lfon a te (7e). This compound was prepared by a pro-
cedure analogous to that of 7a : yield 56%; mp 169-170 °C
(EtOAc-n-pentane); 1H NMR (CDCl3, 400 MHz) δ 1.46 (s, 6H,
2 gem-CH3), 2.78 (s, 3H, SO2CH3), 3.64 (s, 3H, NCH3), 3.86 (s,
3H, 9-OCH3), 4.44 (t, J ) 4.5 Hz, 2H, NCH2CH2), 4.67 (t, J )
4.5 Hz, 2H, NCH2CH2), 5.52 (d, J ) 10 Hz, 1H, H-10), 6.18 (s,
1H, H-7), 6.68 (d, J ) 10 Hz, 1H, H-11), 6.93 (dd, J ) 9, 3 Hz,
1H, H-2), 7.05 (d, J ) 9 Hz, 1H, H-1), 7.37 (d, J ) 3 Hz, 1H,
H-4); 13C NMR (CDCl3, 50 MHz) δ 26.84 (2 gem-CH3), 37.16
(SO2CH3), 40.62 (NCH3), 47.78 (NCH2CH2), 55.61 (OCH3),
67.77 (NCH2CH2), 75.01 (C-9), 85.93 (C-7), 98.86 (C-11a),
105.15 (C-4), 113.96 (C-11c), 117.02 (C-2), 117.38 (C-1), 119.11
(C-4a), 120.84 (C-11), 124.48 (C-10), 136.46 (C-6a), 138.33 (C-
11b), 141.02 (C-12a), 141.93 (C-4b), 154.58 (C-3), 157.99 (C-
7a). Anal. (C23H25N3O5S) C, H, N.
2-[6,9-Dih ydr o-9,9-dim eth yl-1-m eth oxy(1)ben zopyr an o-
[4,3,2-c,d ]p yr a n o[3,2-f]in d a zol-6-yl]-1-eth a n ol Meth a n e-
su lfon a te (7b). This compound was prepared by a procedure
analogous to that of 7a : yield 97%; mp 174-176 °C (EtOAc);
Gen er a l P r oced u r e for th e P r ep a r a tion of th e Am in es
8-27. The appropriate N,N-dialkylaminoethylamine (10 equiv)
was added to a stirred solution of compounds 7a -e in

Xanthenone, Thioxanthenone, and Acridone Derivatives
J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12 2605
anhydrous ethanol. The mixture was stirred at reflux tem-
perature for 12-18 h. Then the mixture was vacuum-
evaporated, and the residue was purified by column chroma-
tography, using a mixture of EtOAc/MeOH (99/1 to 80/20) as
the eluent.
(d, J ) 10 Hz, 1H, H-10), 6.27 (s, 1H, H-7), 6.78 (d, J ) 10 Hz,
1H, H-11), 6.91 (dd, J ) 8, 2 Hz, 1H, H-2), 7.11 (t, J ) 8 Hz,
1H, H-3), 7.43 (dd, J ) 8, 2 Hz, 1H, H-4); 13C NMR (CDCl3, 50
MHz) δ 27.64 (2 gem-CH3), 46.92 [NCH2CH2N(CH3)2], 54.54
[N(CH3)2], 56.31 (OCH3), 57.74 [NCH2CH2N(CH3)2], 76.73 (C-
9), 89.15 (C-7), 100.48 (C-11a), 111.98 (C-11c), 112.73 (C-2),
114.96 (C-4), 115.88 (C-11), 119.11 (C-4a), 123.91 (C-3), 127.65
(C-10), 138.42 (C-4b), 139.90 (C-6a), 144.27 (C-7a), 144.30 (C-
12a), 149.09 (C-1), 156.61 (C-11b). Anal. (C23H25N3O3‚C4H4O4‚
3/2H2O) C, H, N.
Data for Dieth yl-[2-[6,9-dih ydr o-1-m eth oxy-9,9-dim eth -
ylpyrano[3,2-f](1)benzopyrano[4,3,2-c,d]indazol-6-yl]ethyl]-
a m in e (13): yield 97%; mp (fumarate) 174-176 °C (EtOH); 1H
NMR (CDCl3, 400 MHz) δ 1.01 [t, J ) 7 Hz, 6H, N(CH2CH3)2],
1.43 (s, 6H, 2 gem-CH3), 2.63 [q, J ) 7 Hz, 4H, N(CH2CH3)2],
2.93 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2CH3)2], 3.96 (s, 3H,
OCH3), 4.29 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2CH3)2], 5.62 (d,
J ) 10 Hz, 1H, H-10), 6.30 (s, 1H, H-7), 6.80 (d, J ) 10 Hz,
1H, H-11), 6.95 (dd, J ) 8, 2 Hz, 1H, H-2), 7.12 (t, J ) 8 Hz,
1H, H-3), 7.46 (dd, J ) 8, 2 Hz, 1H, H-4); 13C NMR (CDCl3, 50
MHz) δ 11.73 [N(CH2CH3)2], 27.60 (2 gem-CH3), 47.38 [N(CH2-
CH3)2], 47.74 [NCH2CH2N(CH2CH3)2], 52.01 [NCH2CH2N(CH2-
CH3)2], 56.31 (OCH3), 76.74 (C-9), 89.09 (C-7), 100.41 (C-11a),
111.99 (C-11c), 112.69 (C-2), 114.97 (C-4), 115.88 (C-11), 119.19
(C-4a), 123.90 (C-3), 127.61 (C-10), 138.38 (C-4b), 139.92 (C-
6a), 144.26 (C-7a), 144.33 (C-12a), 149.11 (C-1), 156.53 (C-11b).
Anal. (C25H29N3O3‚C4H4O4‚H2O) C, H, N.
Da ta for 6,9-Dih yd r o-1-m eth oxy-9,9-d im eth yl-6-(2-p yr -
r olid in -1-yl-eth yl)p yr a n o[3,2-f](1)ben zop yr a n o[4,3,2-c,d]-
in d a zole (14): yield 95%; mp (fumarate) 228-230 °C (EtOH);
1H NMR (CDCl3, 400 MHz) δ 1.47 (s, 6H, 2 gem-CH3), 1.79
(m, 4H, 3,4-pyrrolidine-H), 2.66 (m, 4H, 2,5-pyrrolidine-H),
3.07 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2)4], 3.97 (s, 3H, OCH3),
4.39 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2)4], 5.61 (d, J ) 10 Hz,
1H, H-10), 6.30 (s, 1H, H-7), 6.79 (d, J ) 10 Hz, 1H, H-11),
6.92 (dd, J ) 8, 2 Hz, 1H, H-2), 7.11 (t, J ) 8 Hz, 1H, H-3),
7.43 (dd, J ) 8, 2 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ
23.49 (3,4-pyrrolidine-C), 27.68 (2 gem-CH3), 48.23 [NCH2-
CH2N(CH2)4], 54.14 (2,5-pyrrolidine-C), 54.89 [NCH2CH2N-
(CH2)4], 56.33 (OCH3), 76.80 (C-9), 89.14 (C-7), 100.57 (C-11a),
111.90 (C-11c), 112.79 (C-2), 114.12 (C-4), 115.85 (C-11), 119.12
(C-4a), 123.92 (C-3), 127.71 (C-10), 138.57 (C-4b), 139.95 (C-
6a), 144.25 (C-7a), 144.27 (C-12a), 149.12 (C-1), 156.71 (C-11b).
Anal. (C25H27N3O3‚C4H4O4‚3/2H2O) C, H, N.
Da ta for 6,9-Dih yd r o-1-m eth oxy-9,9-d im eth yl-6-(2-p i-
p er id in -1-yleth yl)p yr a n o[3,2-f](1)ben zop yr a n o[4,3,2-c,d ]-
in d a zole (15): yield 96%; mp (hydrochloride) 175 °C dec
(EtOH); 1H NMR (CDCl3, 400 MHz) δ 1.44 (s, 6H, 2 gem-CH3),
1.62 (m, 6H, 3,4,5-piperidine-H), 2.49 (m, 4H, 2,6-piperidine-
H), 2.87 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2)5], 3.98 (s, 3H,
OCH3), 4.33 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2)5], 5.61 (d, J )
10 Hz, 1H, H-10), 6.28 (s, 1H, H-7), 6.78 (d, J ) 10 Hz, 1H,
H-11), 6.90 (dd, J ) 8, 2 Hz, 1H, H-2), 7.10 (t, J ) 8 Hz, 1H,
H-3), 7.42 (dd, J ) 8, 2 Hz, 1H, H-4); 13C NMR (CDCl3, 50
MHz) δ 23.95 (4-piperidine-C), 25.55 (3,5-piperidine-C), 27.61
(2 gem-CH3), 46.87 [NCH2CH2N(CH2)5], 54.51 (2,6-piperidine-
C), 56.26 (OCH3), 57.69 [NCH2CH2N(CH2)5], 76.71 (C-9), 89.13
(C-7), 100.46 (C-11a), 111.95 (C-11c), 112.68 (C-2), 114.94 (C-
4), 115.86 (C-11), 119.09 (C-4a), 123.89 (C-3), 127.62 (C-10),
138.37 (C-4b), 139.87 (C-6a), 144.21 (C-7a), 144.22 (C-12a),
149.07 (C-1), 156.59 (C-11b). Anal. (C26H29N3O3‚HCl‚2H2O) C,
H, N.
Data for Dim eth yl-[2-[6,9-dih ydr o-9,9-dim eth ylpyr an o-
[3,2-f](1)b e n zo p y r a n o [4,3,2-c,d ]in d a zo l-6-y l]e t h y l]-
a m in e (8): yield 96%; mp (fumarate) 202-204 °C (EtOH); 1H
NMR (CDCl3, 400 MHz) δ 1.44 (s, 6H, 2 gem-CH3), 2.31 [s,
6H, N(CH3)2], 2.81 [t, J ) 7 Hz, 2H, NCH2CH2N(CH3)2], 4.30
[t, J ) 7 Hz, 2H, NCH2CH2N(CH3)2], 5.60 (d, J ) 10 Hz, 1H,
H-10), 6.27 (s, 1H, H-7), 6.71 (d, J ) 10 Hz, 1H, H-11), 7.11-
7.35 (m, 3H, H-1, H-2, H-3), 7.82 (dd, J ) 8, 1 Hz, 1H, H-4);
13C NMR (CDCl3, 50 MHz) δ 27.76 (2 gem-CH3), 45.66
[N(CH3)2], 47.62 [NCH2CH2N(CH3)2], 58.32 [NCH2CH2N-
(CH3)2], 76.76 (C-9), 88.91 (C-7), 100.19 (C-11a), 113.58 (C-
11c), 115.60 (C-11), 118.21 (C-1), 118.50 (C-4a), 123.06 (C-4),
124.18 (C-3), 127.69 (C-10), 129.64 (C-2), 138.42 (C-4b), 139.90
(C-6a), 144.56 (C-7a), 154.70 (C-12a), 156.54 (C-11b). Anal.
(C22H23N3O2‚C4H4O4‚H2O) C, H, N.
Da ta for Dieth yl-[2-[6,9-d ih yd r o-9,9-d im eth ylp yr a n o-
[3,2-f](1)ben zop yr a n o[4,3,2-c,d ] in d a zol-6-yl]eth yl]a m in e
1
(9): yield 97%; mp (fumarate) 164-165 °C (EtOH); H NMR
(CDCl3, 400 MHz) δ 1.00 [t, J ) 7 Hz, 6H, N(CH2CH3)2], 1.43
(s, 6H, 2 gem-CH3), 2.60 [q, J ) 7 Hz, 4H, N(CH2CH3)2], 2.91
[t, J ) 7 Hz, 2H, NCH2CH2N(CH2CH3)2], 4.25 [t, J ) 7 Hz,
2H, NCH2CH2N(CH2CH3)2], 5.62 (d, J ) 10 Hz, 1H, H-10), 6.26
(s, 1H, H-7), 6.73 (d, J ) 10 Hz, 1H, H-11), 7.10-7.33 (m, 3H,
H-1, H-2, H-3), 7.84 (dd, J ) 7, 1 Hz, 1H, H-4); 13C NMR
(CDCl3, 50 MHz) δ 11.99 [N(CH2CH3)2], 27.68 (2 gem-CH3),
47.50 [N(CH2CH3)2], 48.01 [NCH2CH2N(CH2CH3)2], 52.21
[NCH2CH2N(CH2CH3)2], 76.69 (C-9), 89.06 (C-7), 100.09 (C-
11a), 111.93 (C-11c), 115.62 (C-11), 118.19 (C-1), 118.50 (C-
4a), 123.02 (C-4), 124.16 (C-3), 127.67 (C-10), 129.56 (C-2),
138.25 (C-4b), 139.92 (C-6a), 144.60 (C-7a), 154.67 (C-12a),
156.42 (C-11b). Anal. (C24H27N3O2‚C4H4O4‚3/2H2O) C, H, N.
Da ta for 6,9-Dih yd r o-9,9-d im eth yl-6-(2-p yr r olid in -1-
ylet h yl)p yr a n o[3,2-f](1)b en zop yr a n o[4,3,2-c,d ]in d a zole
(10): yield 96%; mp (fumarate) 171-173 °C (EtOH); 1H NMR
(CDCl3, 400 MHz) δ 1.46 (s, 6H, 2 gem-CH3), 1.76 (m, 4H, 3,4-
pyrrolidine-H), 2.57 (m, 4H, 2,5-pyrrolidine-H), 2.97 [t, J ) 7
Hz, 2H, NCH2CH2N(CH2)4], 4.33 [t, J ) 7 Hz, 2H, NCH2CH2N-
(CH2)4], 5.60 (d, J ) 10 Hz, 1H, H-10), 6.23 (s, 1H, H-7), 6.70
(d, J ) 10 Hz, 1H, H-11), 7.11-7.32 (m, 3H, H-1, H-2, H-3),
7.78 (dd, J ) 8, 1.5 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz)
δ 23.47 (3,4-pyrrolidine-C), 27.69 (2 gem-CH3), 48.01 [NCH2-
CH2N(CH2)4], 54.27 (2,5-pyrrolidine-H), 55.11 [NCH2CH2N-
(CH2)4], 76.71 (C-9), 89.00 (C-7), 100.17 (C-11a), 111.93 (C-
11c), 115.56 (C-11), 118.19 (C-1), 118.44 (C-4a), 123.03 (C-4),
124.16 (C-3), 127.73 (C-10), 129.62 (C-2), 138.37 (C-4b), 139.87
(C-6a), 144.46 (C-7a), 154.67 (C-12a), 156.52 (C-11b). Anal.
(C24H25N3O2‚C4H4O4‚3/4H2O) C, H, N.
Da ta for 6,9-Dih yd r o-9,9-d im eth yl-6-(2-p ip er id in -1-yl-
eth yl)pyr an o[3,2-f](1)ben zopyr an o[4,3,2-c,d]in dazole (11):
1
yield 95%; mp (hydrochloride) 268-270 °C (EtOH); H NMR
(CDCl3, 400 MHz) δ 1.43 (s, 6H, 2 gem-CH3), 1.54 (m, 6H, 3,4,5-
piperidine-H), 2.47 (m, 4H, 2,6-piperidine-H), 2.80 [t, J ) 7
Hz, 2H, NCH2CH2N(CH2)5], 4.31 [t, J ) 7 Hz, 2H, NCH2CH2N-
(CH2)5], 5.61 (d, J ) 10 Hz, 1H, H-10), 6.27 (s, 1H, H-7), 6.71
(d, J ) 10 Hz, 1H, H-11), 7.10-7.32 (m, 3H, H-1, H-2, H-3),
7.83 (dd, J ) 7, 1 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ
24.17 (4-piperidine-C), 25.91 (3,5-piperidine-C), 27.71 (2 gem-
CH3), 47.26 [NCH2CH2N(CH2)5], 54.73 (2,6-piperidine-C), 58.06
[NCH2CH2N(CH2)5], 76.71 (C-9), 89.13 (C-7), 100.14 (C-11a),
111.08 (C-11c), 115.64 (C-11), 118.21 (C-1), 118.50 (C-4a),
123.04 (C-4), 124.18 (C-3), 127.72 (C-10), 129.61 (C-2), 138.30
(C-4b), 139.92 (C-6a), 144.50 (C-7a), 154.70 (C-12a), 156.44 (C-
11b). Anal. (C25H27N3O2‚HCl‚2H2O) C, H, N.
Data for Dim eth yl-[2-[6,9-dih ydr o-9,9-dim eth yl(1)ben zo-
th iopyr an o[4,3,2-c,d]pyr an o[3,2-f]in dazol-6-yl]eth yl]am in e
(16): yield 93%; mp (fumarate) 204-206 °C (EtOH); 1H NMR
(CDCl3, 400 MHz) δ 1.42 (s, 6H, 2 gem-CH3), 2.31 [s, 6H,
N(CH3)2], 2.69 [t, J ) 7 Hz, 2H, NCH2CH2N(CH3)2], 4.28 [t, J
) 7 Hz, 2H, NCH2CH2N(CH3)2], 5.67 (d, J ) 10 Hz, 1H, H-10),
6.32 (s, 1H, H-7), 6.34 (d, J ) 10 Hz, 1H, H-11), 7.23-7.32 (m,
3H, H-1, H-2, H-3), 8.03 (dd, J ) 7, 2 Hz, 1H, H-4); 13C NMR
(CDCl3, 50 MHz) δ 27.75 (2 gem-CH3), 45.61 [N(CH3)2], 47.31
[NCH2CH2 N(CH3)2], 58.08 [NCH2CH2 N(CH3)2], 76.48 (C-9),
91.13 (C-7), 109.45 (C-11a), 115.94 (C-11c), 117.79 (C-11),
123.85 (C-4), 125.34 (C-4a), 125.85 (C-11b), 126.52 (C-1), 126.70
Data for Dim eth yl-[2-[6,9-dih ydr o-1-m eth oxy-9,9-dim eth -
ylpyrano[3,2-f](1)benzopyrano[4,3,2-c,d]indazol-6-yl]ethyl]-
a m in e (12): yield 97%; mp (fumarate) 182-184 °C dec (EtOH);
1H NMR (CDCl3, 400 MHz) δ 1.42 (s, 6H, 2 gem-CH3), 2.32 [s,
6H, N(CH3)2], 2.82 [t, J ) 7 Hz, 2H, NCH2CH2N(CH3)2], 3.95
(s, 3H, OCH3), 4.31 [t, J ) 7 Hz, 2H, NCH2CH2N(CH3)2], 5.60

2606 J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12
Kostakis et al.
(C-3), 128.16 (C-2), 129.01 (C-10), 133.01 (C-12a), 140.14 (C-
6a), 141.38 (C-4b), 154.72 (C-7a). Anal. (C22H23N3OS‚C4H4O4‚
1/4H2O) C, H, N.
N(CH2CH3)2], 2.92 [t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2CH3)2],
3.64 (s, 3H, NCH3), 4.23 [t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2-
CH3)2], 5.51 (d, J ) 10 Hz, 1H, H-10), 6.14 (s, 1H, H-7), 6.78
(d, J ) 10 Hz, 1H, H-11), 7.06 (t, J ) 8 Hz, 1H, H-3), 7.09 (d,
J ) 8 Hz, 1H, H-1), 7.31 (td, J ) 8, 1.5 Hz, 1H, H-2), 7.91 (dd,
J ) 8, 1.5 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ 12.05
[N(CH2CH3)2], 26.97 (2 gem-CH3), 40.83 (NCH3), 47.55 [NCH2-
CH2N(CH2CH3)2, N(CH2CH3)2], 52.11 [NCH2CH2N(CH2CH3)2],
75.04 (C-9), 86.61 (C-7), 99.00 (C-11a), 114.10 (C-11c), 116.01
(C-1), 119.29 (C-4a), 121.05 (C-11), 121.82 (C-3), 122.63 (C-4),
124.69 (C-10), 128.99 (C-2), 136.81 (C-11b), 140.12 (C-6a),
140.96 (C-4b), 144.31 (C-12a), 157.47 (C-7a). Anal. (C25H30N4O‚
HCl‚3/2H2O) C, H, N.
Da ta for Dieth yl-[2-[6,9-d ih yd r o-9,9-d im eth yl(1)ben zo-
th iop yr a n o[4,3,2-c,d ]p yr a n o[3,2-f]in d a zol-6-yl]eth yl]a m -
in e (17): yield 95%; mp (fumarate) 163-165 °C (EtOH); 1H
NMR (CDCl3, 400 MHz) δ 0.95 [t, J ) 7 Hz, 6H, N(CH2CH3)2],
1.45 (s, 6H, 2 gem-CH3), 2.58 [q, J ) 7 Hz, 4H, N(CH2CH3)2],
2.92 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2CH3)2], 4.22 [t, J ) 7
Hz, 2H, NCH2CH2N(CH2CH3)2], 5.63 (d, J ) 10 Hz, 1H, H-10),
6.32 (s, 1H, H-7), 6.35 (d, J ) 10 Hz, 1H, H-11), 7.13-7.30 (m,
3H, H-1, H-2, H-3), 8.05 (dd, J ) 8, 2 Hz, 1H, H-4); 13C NMR
(CDCl3, 50 MHz) δ 11.93 [N(CH2CH3)2], 27.72 (2 gem-CH3),
47.49 [N(CH2CH3)2], 47.67 [NCH2CH2N(CH2CH3)2], 52.04
[NCH2CH2N(CH2CH3)2], 76.38 (C-9), 91.34 (C-7), 109.42 (C-
11a), 115.91 (C-11c), 117.82 (C-11), 123.82 (C-4), 125.22 (C-
4a), 125.94 (C-11b), 126.52 (C-1), 126.70 (C-3), 128.13 (C-2),
129.04 (C-10), 133.01 (C-12a), 140.22 (C-6a), 141.29 (C-4b),
154.66 (C-7a). Anal. (C24H27N3OS‚C4H4O4‚5/4H2O) C, H, N.
Da ta for 6,9-Dih yd r o-9,9-d im eth yl-6-(2-p yr r olid in -1-yl-
et h yl)(1)b en zot h iop yr a n o[4,3,2-c,d ]p yr a n o[3,2-f]in d a -
zole (18): yield 95%; mp (hydrochloride) 235-237 °C (EtOH);
1H NMR (CDCl3, 400 MHz) δ 1.43 (s, 6H, 2 gem-CH3), 1.77
(m, 4H, 3,4-pyrrolidine-H), 2.59 (m, 4H, 2,5-pyrrolidine-H),
2.98 [t, J ) 7 Hz, 2H, NCH2CH2N(CH2)4], 4.32 [t, J ) 7 Hz,
2H, NCH2CH2N(CH2)4], 5.64 (d, J ) 10 Hz, 1H, H-10), 6.34
(d, J ) 10 Hz, 1H, H-11), 6.35 (s, 1H, H-7), 7.10-7.27 (m, 3H,
H-1, H-2, H-3), 8.03 (dd, J ) 7, 2 Hz, 1H, H-4); 13C NMR
(CDCl3, 50 MHz) δ 23.42 (3,4-pyrrolidine-C), 27.75 (2 gem-
CH3), 47.80 [NCH2CH2N(CH2)4], 53.95 (2,5-pyrrolidine-C),
54.56 [NCH2CH2N(CH2)4], 76.48 (C-9), 91.28 (C-7), 109.50 (C-
11a), 115.88 (C-11c), 117.73 (C-11), 123.85 (C-4), 125.22 (C-
4a), 125,79 (C-11b), 126.56 (C-1), 126.70 (C-3), 128.21 (C-2),
129.13 (C-10), 133.04 (C-12a), 140.23 (C-6a), 141.50 (C-4b),
154.81 (C-7a). Anal. (C24H25N3OS‚HCl‚1/2H2O) C, H, N.
Da ta for 6,12-Dih yd r o-9,9,12-tr im eth yl-6-(2-p yr r olid in -
1-ylet h yl)-9H -p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in e
1
(22): yield 97%; mp (hydrochloride) 230-232 °C (EtOH); H
NMR (CDCl3, 400 MHz) δ 1.48 (s, 6H, 2 gem-CH3), 1.79 (m,
4H, 3,4-pyrrolidine-H), 2.60 (m, 4H, 2,5-pyrrolidine-H), 2.99
[t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2)4], 3.68 (s, 3H, NCH3), 4.34
[t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2)4], 5.51 (d, J ) 10 Hz, 1H,
H-10), 6.20 (s, 1H, H-7), 6.70 (d, J ) 10 Hz, 1H, H-11), 7.08 (t,
J ) 8 Hz, 1H, H-3), 7.11 (d, J ) 8 Hz, 1H, H-1), 7.32 (td, J )
8, 1.5 Hz, 1H, H-2), 7.91 (dd, J ) 8, 1.5 Hz, 1H, H-4); 13C NMR
(CDCl3, 50 MHz) δ 22.68 (3,4-pyrrolidine-H), 26.94 (2 gem-
CH3), 40.83 (NCH3), 48.48 [NCH2CH2N(CH2)4], 54.32 (2,5-
pyrrolidine-H), 55.09 [NCH2CH2N(CH2)4], 75.02 (C-9), 86.63
(C-7), 99.01 (C-11a), 114.12 (C-11c), 116.00 (C-1), 119.23 (C-
4a), 120.99 (C-11), 121.84 (C-3), 122.68 (C-4), 124.70 (C-10),
129.00 (C-2), 136.83 (C-11b), 140.10 (C-6a), 140.99 (C-4b),
144.33 (C-12a), 157.53 (C-7a). Anal. (C25H28N4O‚HCl‚1/2H2O)
C, H, N.
Da ta for 6,12-Dih yd r o-9,9,12-tr im eth yl-6-(2-p ip er id in -
1-ylet h yl)-9H -p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in e
1
(23): yield 68%; mp (hydrochloride) 204-206 °C (EtOH); H
NMR (CDCl3, 400 MHz) δ 1.46 (t, J ) 3 Hz, 2H, 4-piperidine-
H), 1.49 (6H, s, 2 gem-CH3), 1.63 (m, 4H, 3,5-piperidine-H),
2.53 (t, J ) 3 Hz, 4H, 2,6-piperidine-H), 2.86 [t, J ) 4.5 Hz,
2H, NCH2CH2N(CH2)5], 3.73 (s, 3H, NCH3), 4.35 [t, J ) 4.5
Hz, 2H, NCH2CH2N(CH2)5], 5.56 (d, J ) 10 Hz, 1H, H-10), 6.21
(s, 1H, H-7), 6.73 (d, J ) 10 Hz, 1H, H-11), 7.12 (t, J ) 8 Hz,
1H, H-3), 7.17 (d, J ) 8 Hz, 1H, H-1), 7.37 (td, J ) 8, 1.5 Hz,
1H, H-2), 7.96 (dd, J ) 8, 1.5 Hz, 1H, H-4); 13C NMR (CDCl3,
50 MHz) δ 23.93 (4-piperidine-C), 25.55 (3,5-piperidine-C),
26.95 (2 gem-CH3), 40.84 (NCH3), 46.50 [NCH2CH2N(CH2)5],
54.55 (2,6piperidine-C), 57.60 [NCH2CH2N(CH2)5], 75.02 (C-
9), 86.70 (C-7), 99.09 (C-11a), 114.08 (C-11c), 116.03 (C-1),
119.15 (C-4a), 120.95 (C-11), 121.83 (C-3), 122.64 (C-4), 124.77
(C-10), 129.07 (C-2), 136.75 (C-11b), 140.10 (C-6a), 141.05 (C-
4b), 144.32 (C-12a), 157.55 (C-7a). Anal. (C26H30N4O‚HCl‚H2O)
C, H, N.
Da ta for 6,9-Dih yd r o-9,9-d im eth yl-6-(2-p ip er id in -1-yl-
et h yl)(1)b en zot h iop yr a n o[4,3,2-c,d ]p yr a n o[3,2-f]in d a -
1
zole (19): yield 97%; mp (fumarate) 172-174 °C (EtOH); H
NMR (CDCl3, 400 MHz) δ 1.43 (s, 6H, 2 gem-CH3), 1.56 (m,
6H, 3,4,5-piperidine-H), 2.46 (m, 4H, 2,6-piperidine-H), 2.79
[t, J ) 7 Hz, 2H, NCH2CH2N(CH2)5], 4.29 [t, J ) 7 Hz, 2H,
NCH2CH2N(CH2)5], 5.64 (d, J ) 10 Hz, 1H, H-10), 6.39 (s, 1H,
H-7), 6.41 (d, J ) 10 Hz, 1H, H-11), 7.16-7.26 (m, 3H, H-1,
H-2, H-3), 8.02 (dd, J ) 7, 1 Hz, 1H, H-4); 13C NMR (CDCl3,
50 MHz) δ 24.19 (4-piperidine-C), 25.94 (3,5-piperidine-C),
27.73 (2 gem-CH3), 47.04 [NCH2CH2N(CH2)5], 54.71 (2,6-
piperidine-C), 57.86 [NCH2CH2N(CH2)5], 76.83 (C-9), 91.41 (C-
7), 109.46 (C-11a), 115.96 (C-11c), 117.85 (C-11), 123.84 (C-
4), 125.20 (C-4a), 125.95 (C-11b), 126.56 (C-1), 126.73 (C-3),
128.16 (C-2), 129.08 (C-10), 131.01 (C-12a), 140.21 (C-6a),
141.31 (C-4b), 154.67 (C-7a). Anal. (C25H27N3OS‚C4H4O4‚5/
2H2O) C, H, N.
Da ta for Dim eth yl-[2-[6,12-d ih yd r o-3-m eth oxy-9,9,12-
tr im eth yl-9H-p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in -6-
yl]eth yl]a m in e (24): yield 50%; mp (hydrochloride) 181-184
1
Da ta for Dim eth yl-[2-[6,12-d ih yd r o-9,9,12-tr im eth yl-
9H-p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in -6-yl]et h yl]-
a m in e (20): yield 29%; mp (hydrochloride) 184-186 °C dec
(EtOH); 1H NMR (CDCl3, 400 MHz) δ 1.44 (s, 6H, 2 gem-CH3),
2.31 [s, 6H, N(CH3)2], 2.82 [t, J ) 4.5 Hz, 2H, NCH2CH2N-
(CH3)2], 3.69 (s, 3H, NCH3), 4.29 [t, J ) 4.5 Hz, 2H, NCH2-
CH2N(CH3)2], 5.51 (d, J ) 10 Hz, 1H, H-10), 6.17 (s, 1H, H-7),
6.70 (d, J ) 10 Hz, 1H, H-11), 7.07 (t, J ) 8 Hz, 1H, H-3), 7.11
(d, J ) 8 Hz, 1H, H-1), 7.33 (td, J ) 8, 1.5 Hz, 1H, H-2), 7.91
(dd, J ) 8, 1.5 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ 26.98
(2 gem-CH3), 40.83 (NCH3), 45.36 [N(CH3)2], 46.94 [NCH2-
CH2N(CH3)2], 57.89 [NCH2CH2N(CH3)2], 75.09 (C-9), 86.48 (C-
7), 99.12 (C-11a), 114.05 (C-11c), 116.03 (C-1), 119.29 (C-4a),
120.96 (C-11), 121.87 (C-3), 122.68 (C-4), 124.74 (C-10), 129.11
(C-2), 136.83 (C-11b), 139.96 (C-6a), 141.17 (C-4b), 144.33 (C-
12a), 157.64 (C-7a). Anal. (C23H26N4O‚HCl‚H2O) C, H, N.
°C (EtOH); H NMR (CDCl3, 400 MHz) δ 1.46 (s, 6H, 2 gem-
CH3), 2.31 (s, 6H, N(CH3)2), 2.82 [t, J ) 4.5 Hz, 2H, NCH2CH2N-
(CH3)2], 3.68 (s, 3H, NCH3), 3.86 (s, 3H, 9-OCH3), 4.30 [t, J )
4.5 Hz, 2H, NCH2CH2N(CH3)2], 5.50 (d, J ) 10 Hz, 1H, H-10),
6.15 (s, 1H, H-7), 6.69 (d, J ) 10 Hz, 1H, H-11), 6.92 (dd, J )
9, 3 Hz, 1H, H-2), 7.08 (d, J ) 9 Hz, 1H, H-1), 7.42 (d, J ) 3
Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ 26.94 (2 gem-CH3),
40.90 (NCH3), 45.53 [N(CH3)2], 47.19 [NCH2CH2N(CH3)2],
55.76 (OCH3), 58.03 [NCH2CH2N(CH3)2], 75.09 (C-9), 85.89 (C-
7), 98.61 (C-11a), 105.34 (C-4), 113.93 (C-11c), 116.99 (C-2),
117.39 (C-1), 119.67 (C-4a), 121.03 (C-11), 124.26 (C-10), 136.91
(C-6a), 138.49 (C-11b), 140.25 (C-12a), 141.21 (C-4b), 154.70
(C-3), 157.71 (C-7a). Anal. (C24H28N4O2‚HCl‚3/4H2O) C, H, N.
Da ta for Dieth yl-[2-[6,12-d ih yd r o-3-m eth oxy-9,9,12-tr i-
m eth yl-9H-p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in -6-yl]-
eth yl]a m in e (25): yield 72%; mp (hydrochloride) 176-178
°C dec (EtOH); 1H NMR (CDCl3, 400 MHz) δ 1.09 [t, J ) 4
Hz, 6H, N(CH2CH3)2], 1.50 (s, 6H, 2 gem-CH3), 2.68 [q, J ) 4
Hz, 4H, N(CH2CH3)2], 2.99 [t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2-
CH3)2], 3.71 (s, 3H, NCH3), 3.91 (s, 3H, 9-OCH3), 4.30 [t, J )
4.5 Hz, 2H, NCH2CH2N(CH2CH3)2], 5.53 (d, J ) 10 Hz, 1H,
Da ta for Dieth yl-[2-[6,12-d ih yd r o-9,9,12-tr im eth yl-9H-
p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]a cr id in -6-yl]e t h yl]-
a m in e (21): yield 83%; mp (hydrochloride) 193-195 °C
1
(EtOH); H NMR (CDCl3, 400 MHz) δ 1.03 [t, J ) 4 Hz, 6H,
N(CH2CH3)2], 1.44 (s, 6H, 2 gem-CH3), 2.60 [q, J ) 4 Hz, 4H,

Xanthenone, Thioxanthenone, and Acridone Derivatives
J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12 2607
H-10), 6.20 (s, 1H, H-7), 6.73 (d, J ) 10 Hz, 1H, H-11), 6.96
(dd, J ) 9, 3 Hz, 1H, H-2), 7.11 (d, J ) 9 Hz, 1H, H-1), 7.46 (d,
6.67 (d, J ) 1 Hz, 1H, H-4), 7.33-7.54 (m, 7H, H-5, H-6,
CH2C6H5), 7.61 (td, J ) 8, ∼0 Hz, 1H, H-7), 8.56 (dd, J ) 8,
∼0 Hz, 1H, H-8). Anal. (C20H14O3S) C, H.
J
) 3 Hz, 1H, H-4); 13C NMR (CDCl3, 50 MHz) δ 11.99
[N(CH2CH3)2], 26.95 (2 gem-CH3), 40.87 (NCH3), 47.53 [N(CH2-
CH3)2, NCH2CH2N(CH2CH3)2], 52.08 [NCH2CH2N(CH2CH3)2],
55.76 (OCH3), 75.01 (C-9), 86.00 (C-7), 98.53 (C-11a), 105.26
(C-4), 110.88 (C-11c), 116.83 (C-2), 117.35 (C-1), 119.81 (C-
4a), 121.10 (C-11), 124.26 (C-10), 136.86 (C-6a), 138.48 (C-11b),
140.25 (C-12a), 141.09 (C-4b), 154.69 (C-3), 157.59 (C-7a). Anal.
(C26H32N4O2‚HCl‚1/2H2O) C, H, N.
3-Acetyloxy-1-[[(4-m eth ylph en yl)su lfon yl]oxy]-9H-th iox-
a n th en -9-on e (33a ). To a solution of 32a (1.14 g, 3.98 mmol)
in dry acetone (30 mL) were added, under argon, p-toluene-
sulfonyl chloride (0.78 g, 4.1 mmol) and anhydrous sodium
carbonate (0.64 g, 6 mmol), and the mixture was refluxed for
40 h. The solvent was then vacuum-evaporated, and the
residue was partitioned between EtOAc and NaOH 10%. The
organic phase was washed with water and brine, dried (Na2-
SO4), and concentrated to dryness. The residue was purified
by flash chromatography eluting with a 70/30 cyclohexane/
CH2Cl2 mixture to afford 33a (1.63 g, 93%): mp 172-173 °C
Da ta for 6,12-Dih yd r o-3-m eth oxy-9,9,12-tr im eth yl-6-(2-
pyr r olidin -1-yleth yl)-9H-pyr an o[2,3-c]pyr azolo[3,4,5-m,n ]-
a cr id in e (26): yield 53%; mp (hydrochloride) 179-182 °C
(EtOH); 1H NMR (CDCl3, 400 MHz) δ 1.48 (s, 6H, 2 gem-CH3),
1.79 (m, 4H, 3,4-pyrrolidine-H), 2.60 (m, 4H, 2,5-pyrrolidine-
H), 2.99 [t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2)4], 3.69 (s, 3H,
NCH3), 3.88 (s, 3H, 9-OCH3), 4.34 [t, J ) 4.5 Hz, 2H, NCH2-
CH2N(CH2)4], 5.50 (d, J ) 10 Hz, 1H, H-10), 6.16 (s, 1H, H-7),
6.69 (d, J ) 10 Hz, 1H, H-11), 6.92 (dd, J ) 9, 3 Hz, 1H, H-2),
7.08 (d, J ) 9 Hz, 1H, H-1), 7.42 (d, J ) 3 Hz, 1H, H-4); 13C
NMR (CDCl3, 50 MHz) δ 23.45 (3,4-pyrrolidine-C), 26.94 (2
gem-CH3), 40.87 (NCH3), 47.49 [NCH2CH2N(CH2)4], 54.14 (2,5-
pyrrolidine-C), 54.58 [NCH2CH2N(CH2)4], 55.72 (OCH3), 75.05
(C-9), 86.19 (C-7), 98.79 (C-11a), 105.30 (C-4), 113.86 (C-11c),
116.99 (C-2), 117.43 (C-1), 119.60 (C-4a), 120.92 (C-11), 124.49
(C-10), 136.76 (C-6a), 138.52 (C-11b), 140.44 (C-12a), 141.50
(C-4b), 154.70 (C-3), 157.89 (C-7a). Anal. (C26H30N4O2‚HCl‚
H2O) C, H, N.
1
(EtOAc); H NMR (CDCl3, 400 MHz) δ 2.28 (s, 3H, COCH3),
2.35 (s, 3H, CH3), 6.88 (d, J ) 2 Hz, 1H, H-4), 6.92 (d, J ) 2
Hz, 1H, H-2), 7.18 (d, J ) 8 Hz, 2H, 3,5-p-toluenesulfonyl-H),
7.36-7.41 (m, 2H, H-5, H-6), 7.46 (td, 1H, J ) 8, ∼0 Hz, H-7),
7.88 (d, J ) 8 Hz, 2H, 2,6-p-toluenesulfonyl-H), 8.32 (dd, 1H,
J ) 8, ∼0 Hz, H-8). Anal. (C22H16O6S2) C, H.
3-Ben zyloxy-1-[[(4-m eth ylp h en yl)su lfon yl]oxy]-9H-th i-
oxa n t h en -9-on e (33b ). This compound was prepared by a
procedure analogous to that of 33a : yield 94%; mp 208-210
1
°C (EtOAc); H NMR (CDCl3, 400 MHz) δ 2.37 (s, 3H, CH3),
5.11 (s, 2H, CH2C6H5), 6.92 (d, J ) 2 Hz, 1H, H-4), 7.00 (d, J
) 2 Hz, 1H, H-2), 7.24 (d, J ) 8 Hz, 2H, 3,5-p-toluenesulfonyl-
H), 7.36-7.44 (m, 7H, H-5, H-6, CH2C6H5), 7.54 (td, J ) 8, ∼0
Hz, 1H, H-7), 7.91 (d, J ) 8 Hz, 2H, 2,6-p-toluenesulfonyl-H),
8.32 (dd, J ) 8, ∼0 Hz, 1H, H-8). Anal. (C27H20O5S2) C, H.
Da ta for 6,12-Dih yd r o-3-m eth oxy-9,9,12-tr im eth yl-6-(2-
p ip er id in -1-yleth yl)-9H-p yr a n o[2,3-c]p yr a zolo[3,4,5-m ,n ]-
a cr id in e (27): yield 68%; mp (hydrochloride) 224-226 °C
2-[4-Ben zyloxy-2H-(1)ben zoth iop yr a n o[4,3,2-c,d ]in d a -
zol-2-yl]-1-eth a n ol (35). To a solution of 33b (1.5 g, 18 mmol)
in dry DMSO (20 mL) was added 2-hydroxyethylhydrazine
(1.22 mL, 18 mmol), and the mixture was heated, under argon,
at 150 °C for 3 h. Upon cooling, the mixture was poured into
water and extracted with CH2Cl2, the organic phase was dried
(Na2SO4), and the solvent was vacuum-evaporated. The resi-
due was purified by column chromatography, using a mixture
of cyclohexane/EtOAc (60/40 to 40/60) as the eluent, to give
1
(EtOH); H NMR (CDCl3, 400 MHz) δ 1.41 (t, J ) 3 Hz, 2H,
4-piperidine-H), 1.47 (s, 6H, 2 gem-CH3), 1.58 (t, J ) 3 Hz,
4H, 3,5-piperidine-H), 2.50 (t, J ) 3 Hz, 4H, 2,6-piperidine-
H), 2.81 [t, J ) 4.5 Hz, 2H, NCH2CH2N(CH2)5], 3.66 (s, 3H,
NCH3), 3.86 (s, 3H, 9-OCH3), 4.31 [t, J ) 4.5 Hz, 2H, NCH2-
CH2N(CH2)5], 5.50 (d, J ) 10 Hz, 1H, H-10), 6.14 (s, 1H, H-7),
6.68 (d, J ) 10 Hz, 1H, H-11), 6.91 (dd, J ) 9, 3 Hz, 1H, H-2),
7.05 (d, J ) 9 Hz, 1H, H-1), 7.41 (d, J ) 3 Hz, 1H, H-4); 13C
NMR (CDCl3, 50 MHz) δ 24.18 (4-piperidine-C), 25.87 (3,5-
piperidine-C), 26.94 (2 gem-CH3), 40.87 (NCH3), 46.90 [NCH2-
CH2N(CH2)5], 54.69 (2,6-piperidine-C), 55.72 (OCH3), 57.89
[NCH2CH2N(CH2)5], 75.02 (C-9), 86.08 (C-7), 98.54 (C-11a),
105.23 (C-4), 113.97 (C-11c), 116.84 (C-2), 117.35 (C-1), 119.78
(C-4a), 121.07 (C-11), 124.26 (C-10), 136.83 (C-6a), 138.49 (C-
11b), 140.25 (C-12a), 141.06 (C-4b), 154.66 (C-3), 157.56 (C-
7a). Anal. (C27H32N4O2‚HCl‚1/4H2O) C, H, N.
1
35 (0.89 g, 78%): mp 142-144 °C (EtOAc); H NMR (CDCl3,
400 MHz) δ 3.28 (t, 1H, D2O exch, OH), 4.11 (t, J ) 5 Hz, 2H,
NCH2CH2), 4.32 (t, J ) 5 Hz, 2H, NCH2CH2), 5.09 (s, 2H,
CH2C6H5), 6.42 (d, J ) 0.5 Hz, 1H, H-5), 6.56 (d, J ) 0.5 Hz,
1H, H-3), 7.25-7.48 (m, 8H, H-7, H-8, H-9, CH2C6H5), 8.32
(dd, J ) 8, ∼0 Hz, 1H, H-10). Anal. (C22H18N2O2S) C, H, N.
1-[[(4-Meth ylph en yl)su lfon yl]oxy]-3-h ydr oxy-9H-th iox-
a n th en -9-on e (34a ). This compound was prepared by a
procedure analogous to that of 35, starting from 33a : yield
1
76%; mp 182 °C (EtOAc); H NMR (CDCl3, 400 MHz) δ 2.38
3-Acetyloxy-1-h ydr oxy-9H-th ioxan th en -9-on e (32a). Ace-
tic anhydride (284 mg, 3.0 mmol) was added to a stirred
solution of 1,3-dihydroxy-9H-thioxanthen-9-one (31; 690 mg,
2.83 mmol)5c and a catalytic amount of triethylamine in dry
dichloromethane. The mixture was stirred at room tempera-
ture for 4 h and then partitioned between dichloromethane
and 1 N HCl. The organic phase was washed with water and
brine, dried (Na2SO4), and concentrated to dryness. The
residue was purified by flash chromatography eluting with a
65/35 cyclohexane/CH2Cl2 mixture to afford 32a (760 mg,
94%): mp 146 °C (EtOAc); 1H NMR (CDCl3, 400 MHz) δ 2.31
(s, 3H, COCH3), 6.47 (d, J ) 1 Hz, 1H, H-2), 6.80 (d, J ) 1 Hz,
1H, H-4), 7.51-7.78 (m, 3H, H-5, H-6, H-7), 8.41 (dd, J ) 8,
∼0 Hz, 1H, H-8), 14.39 (s, 1H, D2O exch, OH-1). Anal.
(C15H10O4S) C, H.
3-Ben zyloxy-1-h yd r oxy-9H-th ioxa n th en -9-on e (32b). To
a solution of 31 (2 g, 8.2 mmol)5c in dry acetone (20 mL) were
added, under argon, benzyl chloride (0.98 mL, 8.4 mmol),
anhydrous sodium carbonate (1.71 g), and anhydrous sodium
iodide (1.43 g), and the mixture was stirred at reflux temper-
ature for 20 h. The solvent was then vacuum-evaporated, the
residue was extracted with CH2Cl2-water, and the organic
phase was dried (Na2SO4) and vacuum-evaporated. The resi-
due was purified by column chromatography, using a mixture
of cyclohexane/EtOAc (80/20) as the eluent, to give 32b (2.57
g, 94%): mp 158-160 °C (EtOAc-Et2O); 1H NMR (CDCl3, 400
MHz) δ 5.16 (s, 2H, CH2C6H5), 6.54 (d, J ) 1 Hz, 1H, H-2),
(s, 3H, CH3), 6.78 (d, J ) 2 Hz, 1H, H-4), 6.90 (d, 1H, J ) 2
Hz, H-2), 7.20 (d, J ) 8 Hz, 2H, 3,5-p-toluenesulfonyl-H), 7.36-
7.44 (m, 2H, H-5, H-6), 7.55 (td, J ) 8, ∼0 Hz, 1H, H-7), 7.89
(d, J ) 8 Hz, 2H, 2,6-p-toluenesulfonyl-H), 8.32 (dd, 1H, J )
8, ∼0 Hz, H-8), 11.05 (s, 1H, D2O exch, OH). Anal. (C20H14O5S2)
C, H.
2-[4-Hydr oxy-2H-(1)ben zoth iopyr an o[4,3,2-c,d]in dazol-
2-yl]-1-eth a n ol (34b). Boron trichloride (1.5 mL, 1 M in
dichloromethane) was added dropwise under argon to a stirred
solution of 35 (140 mg, 0.374 mmol) in dry dichloromethane
(20 mL) with cooling to 0 °C. After 45 min, the cooling bath
was removed, and ethanol (1.5 mL) was added dropwise. The
reaction mixture was concentrated under reduced pressure,
and the residue was purified by flash chromatography eluting
with a 30/70 cyclohexane/EtOAc mixture to afford 34b (82 mg,
1
77%): mp 223-225 °C dec (EtOH); H NMR (DMSO-d6, 400
MHz) δ 3.71 (t, J ) 5 Hz, 2H, NCH2CH2), 4.22 (t, J ) 5 Hz,
2H, NCH2CH2), 6.39 (d, J ) 0.3 Hz, 1H, H-5), 6.41 (d, J ) 0.3
Hz, 1H, H-3), 7.27-7.31 (m, 2H, H-7, H-8), 7.36 (td, J ) 8, ∼0
Hz, 1H, H-9), 7.89 (dd, 1H, J ) 8, ∼0 Hz, H-10). Anal.
(C15H12N2O2S) C, H, N.
2-[4-Ben zyloxy-2H-(1)ben zoth iop yr a n o[4,3,2-c,d ]in d a -
zol-2-yl]-1-eth a n ol Meth a n esu lfon a te (36a ). Methanesulfo-
nyl chloride (773 µL, 10 mmol) was added to a stirred solution
of 35 (1.16 g, 3.1 mmol) and triethylamine (1.58 mL, 11.3
mmol) in dry dichloromethane (60 mL) with cooling to 0 °C.

2608 J ournal of Medicinal Chemistry, 2002, Vol. 45, No. 12
Kostakis et al.
After 30 min, the cooling bath was removed, and the mixture
was stirred at room temperature for 4 h. The reaction mixture
was partitioned between dichloromethane and 1 N sodium
hydroxide. The organic phase was washed with HCl (10%),
water, and brine, then dried (Na2SO4), and concentrated. The
residue was purified by flash chromatography eluting with a
50/50 cyclohexane/EtOAc mixture to afford compound 36a (1.3
g, 93%): mp 153-155 °C (Et2O-n-pentane); 1H NMR (CDCl3,
400 MHz) δ 2.73 (s, 3H, SO2CH3), 4.42 (t, J ) 6 Hz, 2H, NCH2-
CH2), 4.63 (t, J ) 6 Hz, 2H, NCH2CH2), 5.11 (s, 2H, CH2C6H5),
6.41 (d, J ) 0.5 Hz, 1H, H-5), 6.55 (d, J ) 0.5 Hz, 1H, H-3),
7.25-7.48 (m, 8H, H-7, H-8, H-9, CH2C6H5), 8.30 (dd, J ) 8,
0.2 Hz, 1H, H-10). Anal. (C23H20N2O4S2) C, H, N.
reduced by 50% the optical density of treated cells with respect
to untreated controls.
Ack n ow led gm en t. The present study was sup-
ported by a Ministry of Industry, Energy and Technol-
ogy of Greece, Research Grant (Program for Promotion
of Research Scientists-PENED) and a Ministry of Edu-
cation Research Grant (Business Program of Education
and Initial Professional Preparing-EPEAEK).
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2-[4-Hydr oxy-2H-(1)ben zoth iopyr an o[4,3,2-c,d]in dazol-
2-yl]-1-eth a n ol Meth a n esu lfon a te (36b). This compound
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1
74%; mp 186-188 °C (EtOAc); H NMR (400 MHz, CDCl3) δ
2.75 (s, 3H, SO2CH3), 4.40 (t, J ) 6 Hz, 2H, NCH2CH2), 4.59
(t, J ) 6 Hz, 2H, NCH2CH2), 6.40 (d, J ) 0.2 Hz, 1H, H-5),
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To a stirred solution of the amine in anhydrous ethanol was
added a slight excess (5%) of fumaric acid. The resulting
solution was stirred at reflux temperature for 18-43 h and
then allowed to cool at room temperature. The solid was
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diethyl ether, and dried under vacuum (yield 62-80%).
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the new compounds were added to a 5 mM Tris-HCl-0.5 mM
EDTA buffer (pH 8) containing 1 µg/mL calf thymus DNA
(sodium salt) and 1 µg/mL ethidium bromide (all from Sigma,
St. Louis, MO), and fluorescence emission was counted at 600
nm after excitation at 525 nm. The results represent the mean
of two individual experiments and are expressed as EC50, the
concentration of the compound that causes a 50% reduction
in the fluorescence of the calf thymus DNA/ethidium bromide
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