Synthesis and Antimicrobial Activities of 3-Methyl-β-Carboline Derivatives.

The β-carboline alkaloids possess a diverse range of important biochemical effects and pharmacological properties. Sixteen 3-methyl-β-carboline derivatives were synthesized from indole formaldehyde and nitroethane via the Henry reaction, LAH/THF reduction, the Pictet-Spengler reaction and Pd/C/xylene oxidation, including four 1-substituted and twelve 9-substituted 3-methyl- β-carboline derivatives. The structures of all the derivatives were confirmed by 1H NMR, 13C NMR and ESI-MS. Most of these 3-methyl-β-carboline derivatives showed some antibacterial activity.