Some chromeno[4,3-b]quinolines 4a-i were obtained from beta-chloro carboxyaldehydes 3a-c with different aniline derivatives namely, aniline, 4-fluoroaniline, and 2-aminophenol. Surprisingly, 3a-c reacted with 2-aminothiophenol and afforded the chromeno[3,4-c]quinoline derivatives 5a-c. Single-crystal X-ray diffraction studies of 4e and 5b provided good support for the established structure. Compounds 4b and 5b showed significant anti-inflammatory and ulcerogenic score activities compared to that of indomethacin.
Fused pyridine derivatives R 0450Synthesis, X-Ray Structure, and Pharmacological Activity of Some 6,6-Disubstituted Chromeno[4,3-b]-and Chromeno[3,4-c]-quinolines. -A variety of new chromeno[4,3-b]quinolines (V) is synthesized by reaction of chromenecarboxaldehydes (III) with anilines. Surprisingly, (III) react with 2-aminothiophenol to furnish chromeno[3,4-c]quinolines (VII) via extrusion of sulfur from intermediate thiazepines. Compounds (Vb) and (VIIb) show significant antiinflammatory and ulcerogenic activities. -(HEGAB*, M. I.; ABDEL-FATTAH, A.-S. M.; YOUSEF, N. M.; NOUR, H. F.; MOSTAFA, A. M.; ELLITHEY, M.; Arch.
The Vilsmeier-Haack reaction of active methylene compounds led to the formation of b-halo carbaldehydes, which constitute a class of compounds that served as useful intermediates towards construction of different heterocyclic compounds (1). Accordingly, some of b-chlorocarbaldehydes were described to react with phenylhydrazine and 2-mercapto acetic acid and its ethyl ester to give the corresponding pyrazolo and thieno derivatives (2-6). Pawar and Rajput (7) reported the synthesis of 5-anilinothiazolo- [5,4-d]isoxazole from 4-chloro-2-anilinothiazol-5-carbaldehyde with hydroxylamine hydrochloride. As it is known, oxime ethers have found many uses in recent years as nonsteroidal anti-inflammatory drugs (8), insect growth regulators (9), materials with steroidal effect (10), and as antimicrobial agents (11).In continuation of our study on hindered b-chlorocarbaldehydes (6), it seemed to be interesting to react some hindered b-chlorocarbaldehydes with some hydrazines, thiosemicarbazide, and hydroxylamine hydrochloride and to evaluate the pharmacological activity of the new products as anti-inflammatory and anti-ulcerogenic agents. Some new hydrazono 5a,b, thiosemicarbazono 6a-c, and oximo chromenes 7a-c were prepared via the reaction of the corresponding b-chlorocarbaldehyde 3 with hydrazine, aromatic hydrazine, thiosemicarbazide and hydroxylamine hydrochloride, respectively. In addition, ether derivatives 8a-h were prepared from the corresponding aldoximes 7a-c. The new products were tested for anti--inflammatory and ulcerogenic score activities compared to indomethacin.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.