Synthesis of certain indole Derivatives of Pharmaceutical Interest

The biological activity of certain indole derivatives is mentioned . A special interest is focused on the importance of 2-indolecarboxylic acids in both the synthetic and pharmacological fields .An account summarizing the vast literature concerning nomenclature, occurrence, synthetic methods, and physiology-ical activity of pyridoindoles is given .The experimental results attained are crltlcally discussed and a plausible interpretation is advanced in each case.The resent investigation comprises the preparation of the following unavailable starting materials and intermediates:1) 5-chloro-2-nitrotoluene.2) 5-chloro-2-nitrophenylpyruvic acid.3) 5-chloro-2-indolecarboxylic acid.4) enthyl –methylacetoacetate.5)ethyl pyruvate p-chlorophenylhydrazone.6) ethyl 5-chloro-2-indolecarboxylate.7) 2-indolecarboxhydrazide.8) 5-chloro-2-indolecarboxhydrazide.9) 5-chloro-2-hydroxymethylindole.10) 5-chloroindole-2-carboxaldehyde.11) p-chlorophenylhydrazine.