Synthesis and antimicrobial activity of new derivatives of pyrano[4'',3'':4',5']pyrido[3',2':4,5]thieno[3,2-d]pyrimidine and new heterocyclic systems

Samvel N. Sirakanyan, Domenico Spinelli, Athina Geronikaki, Viktor G. Kartsev, Elmira K. Hakobyan, Anush A. Hovakimyan
2019 Figshare  
Taking into account previously obtained biological results on some polyheterocyclic compounds (containing different heteroatoms) and in particular on several 8-amino-5-isopropyl-2,2-dimethyl-10-(methylthio)-1,4-dihydro-2H-pyrano[4",3":4',5']pyrido[3',2':4,5]thieno[3,2-d]pyrimidines Ia-v we have carried out the synthesis of twentyone 8-amino-5-isobutyl-2,2-dimethyl-10-(methylthio)-1,4-dihydro-2H-pyrano[4",3":4',5']pyrido[3',2':4,5]thieno[3,2-d]pyrimidines 6. Therefore we have slightly modified
more » ... slightly modified the structure of the previously studied I introducing at C-5 an isobutyl group instead of the previously examined isopropyl ones in order to see if this variation (changing a little the lipophilicity) will affect the biological activity. Furthermore thieno[3,2-d]pyrimidine-8-thione 7 and their S-alkylated 8 were synthesized. Finally by alkylation of 5-isobutyl-2,2-dimethyl-10-thioxo-1,4,10,11-tetrahydro-2H-pyrano[4",3":4',5']pyrido[3',2':4,5]thieno[3,2-d]pyrimidin-8(9H)-one 3 with alkyl dichlorides (bifunctional reagents) we realized the cyclization of a thiazole or thiazine ring on the [b] side of the pyrimidine ring with formation of the new condensed pentaheterocyclic systems: pyrano[4",3":4',5']pyrido[3',2':4,5]thieno[3,2-d][1,3]thiazolo[3,2-a]pyrimidin-8-one 11 and pyrano[4"',3"':4",5"]pyrido[3",2":4',5']thieno[3',2':4,5]pyrimido[2,1-b][1,3]thiazin-8-one 12. It was found that some of the synthesized compounds showed interesting antimicrobial activity (by agar diffusion method) against some gram-positive and gram-negative bacilli strains. On the basis of some our previous results we have carried out the synthesis of several new polyheterocyclic compounds with the aim of studying their biological activity. Notwithstanding predictions from in silico tests furnished negative results, we have examined their antimicrobial activity (by agar diffusion methods) observing that s [...]
doi:10.6084/m9.figshare.8003654 fatcat:ge3k2uimw5a45cwcumkzjaa2vm