Synthesis of novel and biologically potent heteropolycyclics containing bridge head nitrogen

• Published in: Journal of heterocyclic chemistry 2010-09, Vol.47 (5), p.1188-1199
• Main Authors: Gupta, Poonam, Gupta, Shallu, Sachar, Anand, Sharma, R. L.
• Format: Article
• Language: English
• ISSN: 0022-152X; 1943-5193
• DOI: 10.1002/jhet.465

A facile one pot synthesis of 2,3,4,5‐tetrahydropyrido [1,2‐a] [1,3] diazepine‐2,5‐dione 2 and 3,4‐dihydro‐2H‐pyrido [1,2‐a] pyrimidine‐2,4‐dione 3 has been achieved. Condensation of 3 with o‐aminobenzaldehydes produced the linear product 4 and not the angular one 5. Cyclocondensation of 3 with 1,5‐diketones afforded a tricyclic linear system 6, a bis assembly system 7 and two novel heterotetracyclic nitrogen bridged linear systems 8 and 10. Condensation of o‐aminobenzaldehydes with 2 produced a novel linear system 12 and a new doubly fused hexacyclic system 11. Cyclodehydration of 2 with 1,2‐dicarbaldehydes produced 1, 13, and a new heterotetracyclic nitrogen bridged system 14. Condensation of 3 with aromatic aldehydes in presence of ethylene glycol as solvent without the use of catalyst generated the doubly nitrogen bridged linear pentacyclic systems 15, 16, 17. The synthesized compounds have been adequately characterized and screened for bronchodilatory and antimicrobial activities with promising results. J. Heterocyclic Chem., (2010).