239-15-6Relevant articles and documents
Total synthesis of new indolo[2,3-a]quinolizine alkaloids sempervirine type, potential pharmaceuticals
Lipińska, Teodozja M.
, p. 5736 - 5747 (2007/10/03)
Total synthesis of the two series of new pentacycilc cycloalk[g]indolo[2,3-a]quinolizine alkaloids (modified sempervirine possessing the wide range of activity), has been elaborated in five steps from 5-acetyl-3-methylthio-1,2,4-triazine (obtained from the simple acyclic materials). In the two key steps: inverse electron demand Diels-Alder reaction of precursor with cyclic enamines and the following Fischer indolization of 3-acetyl-1-methylthiocycloalka[c]pyridines, the AB-DE synthons, has been obtained. The final stages: desulfuration, and formation of the C-ring via the Gribble method have led to the expected zwitterionic alkaloids. Model syntheses of the indolopyridocoline and its methoxy analogue from 2-acetylpyridine have been performed for investigation of the microwave-induced Fischer synthesis of sensitive indoles and for obtaining compounds for comparative study of spectroscopic data.
A DIRECTED METALATION ROUTE TO THE ZWITTERIONIC INDOLE ALKALOIDS. SYNTHESES OF INDOLOQUINOLIZINE, FLAVOPEREIRINE, FLAVOCARPINE, AND DIHYDROFLAVOPEREIRINE
Gribble, Gordon W.,Johnson, David A.
, p. 5259 - 5262 (2007/10/02)
A protocol involving beta-lithiation of 2-(2-pyridinyl)indoles (4->5) and subsequent reaction with bromoacetaldehyde or oxirane has led to syntheses of the alkaloids indoloquinolizine (1), flavopereirine (2), flavocarpine (21), and dihydroflavopere
