Synthesis and characterization of 2-mercapto-N-methyl imidazole substituted benzimidazole derivatives and investigation of their effect on production of plantlets in <i>Oncidium</i> Gower Ramsey

Abstract

A series of benzimidazole derivatives (5a-c) were synthesized by coupling 5-substituted 2-chloromethyl benzimidazole (3a-c) with 2-mercapto-N-methyl imidazole. The synthesized compounds were characterized by infra-red (IR), nuclear magnetic resonance (NMR) and elemental analyses. Further, the synthesized compounds were tested on plantlet production from protocorm like bodies (PLBs) sections of Oncidium. PLBs sections were cultured on half strength modified Murashige and Skoogs (MS) medium alone and also modified MS medium supplemented with the synthesized chloro, methyl and nitro derivatives individually at 2 or 5 µM concentrations. Among these three compounds, PLBs sections cultured on medium supplemented with nitro compound (5c) at 5 µM concentration produced maximum number (95) of plantlets. 

 Key words: Benzimidazole derivatives, protocorm like bodies, plant growth regulators, 2-mercapto-N-methyl imidazole.

Abbreviation:

PLBs, Protocorm like bodies; CMNP, 5-chloro-3-methyl-4-nitro-1H-pyrazole; ZnAAC, zinc-amino acid complexes; TIBA, 2,3,5-triiodobenzoic acid; PCIB, 2-(p-chlorophenoxy)-2-methylpropionic acid; IR, infra-red; NMR, nuclear magnetic resonance