Synthesis, photochemical E (trans)-->Z (cis) isomerization and antimicrobial activity of 2-chloro-5-methylpyridine-3-olefin derivatives.

2-Chloro-5-methylpyridine-3-olefin derivatives (3a-e) have been synthesized from 2-chloro-5-methylnicotinaldehyde (1) and studied their photochemical E (trans)-->Z (cis) isomerization upon direct irradiation and triplet sensitized excitation for the first time. The triplet sensitized excitations of the compounds yielded high Z (4a-e) isomer composition, whereas the direct excitation results in less Z (4a-e) isomer composition, indicating triplet pathway is very efficient in converting the E (trans)-->Z (cis) isomer. Thus synthesized E (3a-c and 3e) and generated Z (4a-c and 4e) isomers were tested for antimicrobial activity. Antifungal activity of these pyridine derivatives are closely comparable to the standard used.

Synthesis of multisubstituted quinolines from Baylis-Hillman adducts obtained from substituted 2-chloronicotinaldehydes and their antimicrobial activity.

Baylis-Hillman acetates were synthesized from substituted 2-chloronicotinaldehydes and were conveniently transformed into multisubstituted quinolines and cyclopenta[g]quinolines on reaction with nitroethane or ethyl cyanoacetate via a successive S(N)2'-S(N)Ar elimination strategy. Thus, synthesized quinolines were evaluated for antimicrobial activity and found having substantial antibacterial and antifungal activity.

Anti-malarial activity of Baylis-Hillman adducts from substituted 2-chloronicotinaldehydes.

New Baylis-Hillman adducts are synthesized based on substituted 2-chloronicotinaldehydes and screened for their in vitro anti-malarial activity against chloroquine sensitive and chloroquine resistant Plasmodium falciparum. Out of the six new compounds synthesized and screened, 2b, 2c and 2d compounds showed substantial anti-malarial activity.