A synthesis of racemie saphenic acid is described. From this acid 9 ester derivatives of saphenamycin were prepared. Those with aromatic acid components showed high activity against many Gram-positive and some Gram-negative bacteria. Of the esters with aliphatic acid moieties only the acetate and, to a lesser extent, the butyrate showed considerable anti-bacterial activities, whereas esters wit...

A known norcembranoidal diterpene, 5-episinuleptolide (1), along with a new analogue, 4α-hydroxy-5-episinuleptolide (2), were isolated from a cultured-type soft coral Sinularia numerosa. The structures of 1 and 2 were elucidated on the basis of spectroscopic methods and by comparison of the data with those of the related metabolites. Cytotoxicity of metabolites 1 and 2 against a panel of tumor ...

New aryl-hydrazinyl-1,3-selenazole and aroyl-hydrazonyl-1,3-selenazoles were synthesized via Hantzsch type condensation reactions of selenosemicarbazides with α-halogenocarbonyl derivatives, under classical versus microwave heating conditions. Excellent yields and shorter reaction times were obtained under irradiation conditions. The structures of the synthesized compounds were assigned based o...

215 1 Assistant Professor and CCRF Research Chair in Rehabilitation Epidemiology, School of Physical and Occupational Therapy, Faculty of Medicine, McGill University, 3630 Promenade Sir-William-Osler Hosmer House, Room 205, Centre de réadaptation Constance-Lethbridge Centre de Recherche Interdisciplinaire en Readaptation (CRIR) Montreal, Quebec, Canada H3G 1Y5 Tel. #: (514) 398-4400 ext 00849 F...

Ascaridol is the active principle of the American wormseed Chenopodium anthelminticum L. We isolated ascaridol from a commercial preparation of Chenopodium oil and analyzed its activity against different tumor cell lines in vitro (CCRF-CEM, HL60, MDA-MB-231). Multidrug-resistant (MDR) counterparts of these cell lines express differentially the MDR-conferring ATP-binding cassette transporter gen...

ABSTRACT A series of new benzimidazole and benzotriazole derivatives containing a tetrazole moiety was synthesized by N-alkylation of 5-aryltetrazole with 4,5,6,7-tetrabromo-1-(3-chloropropyl)-1H-benzimidazole and 4,5,6,7-tetrabromo-2-(3-chloropropyl)-2H-benzotriazole. The reaction was regioselective and mostly 2,5-disubstituted tetrazole derivatives were obtained. The effect of all synthesized...

The role of MRP4 and MRP5 transporters in the acyclic nucleoside phosphonate PMEDAP efflux was studied in vitro (CCRF-CEM cells) and in vivo (spontaneous transplantable T-cell lymphoma of SD/Cub inbred rats). The increased resistance against the cytostatic agent PMEDAP during longterm treatment was found to be associated with overexpression of MRP4 and MRP5 genes. The course of both gene activa...

A new triterpene diastereomer, 1, of the previously reported 3beta,6beta,19alpha-trihydroxy-urs-12-en-28-oic acid-24-carboxylic acid methyl ester was obtained from the stem bark of Omphalocarpum elatum Miers (Sapotaceae) along with a-amyrin acetate (2), spinasterol (3), spinasterol 3-O-beta-D-glucopyranoside (4), and tormentic acid (5). The structures of the isolates were established on the bas...

Thymidylate synthetase activity of a human lymphoblastic cell line, CCRF-CEM, was elevated by the addition of methotrexate to the culture medium and was lowered when cytosine arabinoside was added. The simultaneous addition of both drugs resulted in levels of enzyme activity intermediate between those observed for each drug alone. The level of enzyme activity could be modulated by varying the r...