Synthetic studies relevant to biosynthetic research on vitamin B12. Part 2. Syntheses of C-methylated chlorins via lactams
作者:Alan R. Battersby、Christopher J. R. Fookes、Roger J. Snow
DOI:10.1039/p19840002733
日期:——
C-Methylatedchlorins have been synthesised by two approaches. For one, ring-B and ring-C of the final chlorin were built sequentially onto a thiolactam system which acted as the A-D component. The preferred alternative method involved joining together a lactam (a dihydropyrromethenone) as A-D precursor with a pyrromethane as the B-C component, the final ring-closure to the chlorin being carried out
Synthetic studies relevant to biosynthetic research on vitamin B12. Part 1. Syntheses of C-methylated chlorins based on 1-pyrrolines (3,4-dihydropyrroles)
作者:Alan R. Battersby、Christopher J. R. Fookes、Roger J. Snow
DOI:10.1039/p19840002725
日期:——
Two routes are explored for the synthesis of chlorins geminally substituted in the reduced ring; both involve cyclisations of 1-pyrroline (3,4-dihydropyrrole) systems promoted by copper(II) salts. In the preferred synthesis, a pyrrolomethyl-1-pyrroline is combined with a 5-bromo-5′-bromomethyl-pyrromethene; though not high yielding, this approach involves few steps from readily prepared building blocks