Publications by authors named "R A Izydore"

The synthesis of the title compounds was carried out by reacting dicarboxylic acid chlorides with oximes in the presence of excess triethylamine. Disubstituted malonyl chlorides gave 2-alkenyl-4,4-dialkyl-3,5-isoxazolidinediones (8a-f) and 2,2'-ethylidene-bis[4,4-dialkyl-3,5-isoxazolidinedione]s (9a-f). Compounds 9 were formed from 8 and its N-unsubstituted 3,5-isoxazolidinedione decomposition product.

View Article and Find Full Text PDF

Bioactivity-directed fractionation of an extract of the leaves of Alvaradoa haitiensis, using the KB (human oral epidermoid carcinoma) cell line, led to the isolation and identification of 10 new anthracenone C-glycosides, alvaradoins E-N (1-10), along with the known compound chrysophanol (11). The cytotoxicity of all compounds was evaluated, and preliminary structure-activity relationships are suggested. The most potent compounds in the in vitro assays (1 and 2) were evaluated in vivo versus the P388 (murine lymphocytic leukemia) model, and alvaradoin E (1) showed antileukemic activity (125% T/C) at a dose of 0.

View Article and Find Full Text PDF

3-Ethoxycarbonyl-5-phenyl-1, 3a, 4, 5, 6, 6a-hexahydropyrrolo[3,4-c]pyrazole-4, 6-dione, 2, 2, 6, 6-tetraethyl-1H, 5H-pyrazole[1, 2-a]pyrazole-1, 3, 5, 7-[2H, 6H]-tetraone and 6-ethoxycarbonyl-3-phenyl-3-azabicyclo[3.1.0] hexane-2, 4-dione demonstrated potent cytotoxic activity in the human Tmolt3, Tmolt4 and HL-60 leukemia screens, HuT-78 lymphoma and HeLa suspended uterine carcinoma cell lines.

View Article and Find Full Text PDF

The observation that expression of the IMPDH gene is tightly linked with cellular proliferation and transformation has led to an interest in developing inhibitors that deplete intracellular guanine nucleotide pools. IMPDH exists as 2 isoforms, one of which is induced in tumor cells, type II and thus has led to new interest in this target for the design of isoform-selective anticancer chemotherapeutic agents. Several classes of IMPDH inhibitor are now in use or under development; however, only the 1,5-diazabicyclo[3.

View Article and Find Full Text PDF

The 3,5-pyrazolidinediones proved to be potent cytotoxic agents against the growth of a number of murine and human tumor cell lines, e.g. human THP-I monocytic leukemia, Hut-78 lymphoma, MCF-7 breast effusion, A549 lung carcinoma, U87MG glioma, Hela uterine and A431 epidermoid skin cancer.

View Article and Find Full Text PDF