Nitrogen-containing compounds from the moss Fontinalis squamosa
摘要:
The alkaloid harmol and its hitherto unknown propionic acid derivative as well as a new amino acid derivative fontinalin were isolated from the watermoss Fontinalis squamosa. The structures have been elucidated spectroscopically and by independent chemical synthesis. (C) 1998 Elsevier Science Ltd. Ail rights reserved.
PTC‐Promoted Japp–Klingmann Reaction for the Synthesis of Indole Derivatives
摘要:
Indole derivatives have been efficiently synthesized from ethyl 2-phenylhydrazono-5-phthalimido-pentanoate and its derivatives, which were obtained by Japp-Klingmann reaction under phase-transfer catalytic (PTC) conditions. Several different phase-transfer catalysts were investigated and dimethyldioctadecyl ammonium chloride (DMDOA) was found to promote this reaction efficiently. Using DMDOA as the PTC, aryl hydrazones were obtained in yields of 90%. The pure aryl hydrazones were then efficiently cyclized to indole derivatives in yields of more than 80%.