Showing papers by "Hanafi H. Zoorob published in 2012"

Efficient regioselective synthesis and potential antitumor evaluation of isoxazolo[5,4-b]pyridines and related annulated compounds.

Abstract: The reaction of 5-amino-3-methylisoxazole with appropriate α,β-unsaturated ketones gave the corresponding isoxazolo[5,4-b]pyridines. Treatment of 1 with 2,6-dibenzylidenecyclohexanone or 2-benzylidenedimedone afforded the corresponding isoxazolo[5,4-b]quinoline derivatives. 4,6,8,9-Tetrahydroisoxazolo[5,4-b]quinolin-5-one derivative was also obtained by multicomponent condensation reaction of 1 with dimedone and benzaldehyde. Heterocyclic annulation of the isoxazolo[5,4-b]pyridine system was achieved via reaction of 1 with benzylidene derivatives of indandione, quinuclidone, pyrazolone, and oxazolone. A representative of some newly synthesized compounds was evaluated as antitumor agents.

Synthesis and biological evaluation of some new Thiazolo[3,2- a ][1,3,5]triazine derivatives

Abstract: 2-Iminothiazolidin-4-one (1) was utilized for the synthesis of several new thiazolo[3,2-a][1,3,5]triazine derivatives. 3-Phenyl-3,4-dihydro-2H-thiazolo[3,2-a][1,3,5]triazin-6(7H)-one (2) was prepared according to Mannich procedure. Both compounds 1 and 2 reacted with aromatic aldehydes to afford arylidene derivatives 3–7. Compounds 5–7 were obtained through another two routes of preparation, first when applying Mannich reaction to compounds 3 and 4 and second by reacting compounds 2 with activated olefins 11 catalyzed by triethylamine, also, the reaction of 2 with bis arylidene 16 afforded compound 18. Compound 2 reacted with both mono and di-aromatic diazonium salts to furnish 2-aryl-azothiazolo[3,2-a]triazines 20 and 21 or bis[2-azothiazolo[3,2-a]triazine]phenylene 22, respectively. Thiocarbamoyl derivatives 25 and 26 were prepared through the reaction of active methylene and imino group in 1 with phenylisothiocyanate and carbon disulfide, respectively. Structures confirmation, geometry, and biological evaluation were applied for the newly prepared compounds.

Utility of Cyclododecanone as Synthon to Synthesize Fused Heterocycles

Abstract: Ethyl 2-oxocyclododecanecarboxylate (1), and 2-(hydroxyl-methylene)cyclododecanone (7) were used as key intermediates for synthesis of macrocyclic systems incorporating either fused or exocyclic nitrogen heterocycles of differ- ent ring sizes. Ring enlargement was also implemented.

Efficient Regioselective Synthesis and Potential Antitumor Evaluation of Isoxazolo[5,4‐b]pyridines and Related Annulated Compounds.

Abstract: A variety of isoxazolopyridine derivatives and related compounds are synthesized starting from 5-amino-3-methylisoxazole (I).