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flash chromatography (CH2Cl2–EtOAc or n-hexane–EtOAc as solvent) of the
residue.
tiviral activity of such a class of compounds. Quite recently,
cosalane, which possesses a dichlorinated disalicylmethane
fragment in the molecule, has been reported as an anti-HIV
agent. In this fragment, one can also find 4,4Ј-dihydroxy-
In the case of 5a, the product was purified by recrystallization from diiso-
propylether. The structures of the products were determined by elemental
analysis and spectroscopic methods. The yields and physical data are sum-
bisphenol moiety.6) It is noteworthy that these simple bisphe- marized in Tables 1—4.
Compound 11: Pale yellow oil. HR positive ion FAB-MS: Calcd for
nol derivatives showed considerably high antiviral activity.
On the basis of our observation, synthetic trials are being
made on triphenylmethane-type 4,4Ј-dihydroxybisphenols.
Regarding the molecular modification, there are many com-
binations of starting aromatic aldehydes and phenols. The
synthetic methodologies have already been reported.4) The
results of molecular modification of the prototype 10 and bi-
ological screening will be described elsewhere.
C18H19O (MϩH)ϩ: 251.1436. Found: 251.1436. 1H-NMR (CDCl3) d: 2.70—
2.76 (4H, m, PhCH2CH2–), 3.57 (2H, s, PhЈCH2–), 6.57—6.60 (1H, m,
–CHϭCϽ), 7.09—7.16 (5H, m, ortho-ArЈH and ArH, para-ArЈH), 7.19—
7.23 (3H, m, para-ArH, meta-ArЈH), 7.26—7.29 (2H, m, meta-ArH),
9.43 (1H, s, CHO). 13C-NMR (CDCl3) dC: 29.61 (PhЈCH2–), 30.95
(PhCH2CH2–), 34.38 (PhCH2CH2–), 126.04 (para-C of PhЈ), 126.33 (para-C
of Ph), 128.27, 128.30, 128.40, 128.55 (ortho- and meta-C of Ph and PhЈ),
139.01 (C1Ј of PhЈ), 140.40 (C1 of Ph), 142.81 (–CHϭCϽ), 154.55
(–CHϭCϽ), 194.41 (CHO).
Antiviral Activity Assay The antiviral activities of the compounds were
measured by the plaque reduction assays5) as described below. Confluent
monolayers of Vero cells (5ϫ105 cells) in 6-well plastic plates were infected
with 100 PFU of HSV-l (KOS). After 1 h adsorption period at 37 °C, the cul-
tures were overlaid with 2 ml of DULBECCO's modified Eagle minimum es-
sential medium (DMEM) containing 2% heat-inactivated fetal calf serum
and various concentrations of the target compounds. The cultures infected
with HSV-1 were incubated in a CO2 incubator, fixed with formalin and
stained with crystal violet in methanol at 3 d after infection. After washing
with water and drying, the plaque numbers were counted. Calculated EC50
values for the tested compounds are summarized in Table 5.
Experimental
Melting points were determined by a micro melting point apparatus
(Yanagimoto MP-S3) without correction. IR spectra were measured with a
Shimadzu FTIR-8100 IR spectrophotometer. The absorption bands attribut-
able to OH, CH, aromatic CϭC, and C–O bonds were observed at 3300—
3430, 2860—2990, 1580—1640, and l150—1220 cmϪ1, respectively. Low-
and high-resolution mass spectra (LR-MS and HR-MS) were taken with a
JEOL JMS HX-110 double-focusing model equipped with a FAB ion source
interfaced with a JEOL JMA-DA 7000 data system. 1H- and 13C-NMR spec-
tra were obtained on a JEOL JNM A-500 or GX-400. Chemical shifts were
expressed in d ppm downfield from an internal tetramethylsilane (TMS) sig-
nal for 1H-NMR and the carbon signal of the corresponding solvent [CDC13
(77.0 ppm) and DMSO-d6 (39.5 ppm)] for 13C-NMR. Microanalyses were
performed with a Yanaco MT-6 CHN corder. Routine monitoring of reac-
tions was carried out using precoated Kieselgel 60F254 plates (E. Merck).
Flash column chromatography was performed using a silicagel (Fuji Silysia
FL-60D) with a UV detector. Commercially available starting materials were
used without further purification.
General Procedure for the Preparation of 2,2
-Dihydroxybisphenols
(5a—d) Under a nitrogen stream a solution of the selected phenol (1)
(20 mmol) in Et2O (50 ml) was added dropwise to a solution of 3 M EtMgBr
(6.7 ml, 20 mmol) in Et2O (40 ml) with stirring at room temperature, and the
mixture was allowed to stand for 20 min, then Et2O was removed under vac-
uum. After addition of CH2Cl2 (300 ml) to the residue, a solution of the se-
lected aldehyde (2—4) (5 mmol) in CH2Cl2 (100 ml) was added with stir-
ring. The resulting mixture was refluxed with or without sonication (see
Table 1). The reaction was quenched with saturated aqueous NH4Cl
(100 ml), and the mixture was extracted with EtOAc (3ϫ100 ml). The com-
bined extracts were dried (MgSO4) and concentrated under reduced pres-
sure. The desired compounds (5a—d) and by-products (11) were purified by
Acknowledgment We thank Ms. Y. Iwase, Mr. H. Harazono, and Ms. J.
Honda of the Faculty of Pharmaceutical Sciences, Fukuoka University for
NMR, MS, and elemental analyses. We also thank Ms. M. Inada and Mr. J.
Taniguchi for their technical assistance.
References
1) Sato T., Kise H., Yukagaku, 37, 166—170 (1988).
2) Asakura K., Matsumura S., Yoshikawa S., Yukagaku, 37, 265—270
(1988).
3) Yamato M., Hashigaki K., Yasumoto Y., Sakai J., Luduena R. E.,
Banerjee A., Tsukagoshi S., Tashiro T., Tsuruo T., J. Med. Chem., 30,
1897—1900 (1987).
4) Mibu N., Sumoto K., Chem. Pharm. Bull., 48, 1810—1813 (2000).
5) Schinazi R. F., Peters J., Williams C., Chance D., Nahmias A. J., An-
timicrob. Agents Chemother., 22, 499—507 (1982).
6) Santhosh K. C., Paul G. C., De Clercq E., Pannecouque C., Witvrouw
M., Loftus T. L., Turpin J. A., Buckheit R. W., Jr., Cushman M., J.
Med. Chem., 44, 703—714 (2001).