Antibacterial activity of 1-methyl-7-methoxy-beta-carboline and its phenacyl and coumarine analogues.

Antibacterial activity of 1-methyl-7-methoxy-beta-carboline (harmaline) and its phenacyl and coumarine analogues 1-(3-nitro-phenyl)-(2-(7-methoxy-1-methyl-1,3,4,9-tetrahydro-beta-carbolin-2-yl)-ethanone (II), 1-(3,4-dihydroxy-phenyl)-2-(7-methoxy-1-methyl-1,3,4,9-tetrahydro-beta-carbolin-2-yl)-ethanone (III) 7-(methoxy-beta-carboline),15-24,de-hydro(19,20-dimethoxy)coumarine (IV), 7-(methoxy-beta-carboline)15-24,dehydro(20-methoxy)coumarine (V) were studied by disc diffusion method. All compounds were tested against three gram positive and four gram-negative bacteria. Parent compound showed good activity. All compounds revealed better results against gram positive as compared to gram-negative bacteria. 1-(3,4-Dihydroxy-phenyl)-2-(7-methoxy-1-methyl-1,3,4,9-tetrahydro-beta-carbolin-2-yl)-ethanone (III) was found most potent compound showing broad spectrum activity when compared with all synthesized analogues. Coumarine analogues showed more or less same activity indicating that number and position of methoxy groups are not important regarding antimicrobial activity.

Effect of diazepam on the CNS excitation and behavioural changes induced by harmaline and its newly synthesized analogues.

The neuropharmacologic profile of harmala alkaloids has been studied and found to have central effects like convulsions, catalepsy, or altered startle response. In number of studies the effects of diazepam, on harmaline and other beta carboline containing compounds-induced tremors were investigated. The present study was undertaken to examine the effect of diazepam on pretreated animals with harmaline and its synthesized phenacyl and coumarine analogues. Diazepam successfully inhibited the tremor and convulsions and attenuated the other behavioural response produced by harmaline and its derivatives.

Synthesis of some phenacyl derivatives of 1-methyl-7-methoxy-beta-carboline and their behavioural study.

In the present study two phenacyl derivatives of Harmaline; 2-(7-Methoxy-1-methyl-1,3,4,9-tetrahydro-beta-carbolin-2-yl)-1-(3-nitro-phenyl)-ethanone and 1-(3,4-Dihydroxy-phenyl)-2-(7-methoxy-1-methyl-1,3,4,9-tetrahydro-beta-carbolin-2-yl)-ethanone were synthesized and evaluated for their effect on behaviour of mice, only meta-nitro phenacyl derivative showed activity, which can be compared with parent compound.