139260-71-2Relevant articles and documents
Synthesis of 11-Amino-substituted-9-methoxy-5-methyl-6H-pyridocarbazoles
Praly-Deprez, Isabelle,Rivalle, Christian,Huel, Christiane,Belehradek, Jean,Paoletti, Claude,Bisagni, Emile
, p. 3165 - 3171 (2007/10/02)
A route to 11-amino-substituted-6H-pyridocarbazoles has been studied.Thus, condensation of 2-(4-lithiopyridine-3-yl)-4,4-dimethyloxazoline with 2-acetyl-5-methoxy-1-phenylsulphonylindole led to a low yield of the expected alcohol, which upon hydrolysis gave a complex mixture.A better starting building block was 4-acetyl-N,N-diisopropylnicotinamide obtained either from N,N-diisopropyl-4-lithionicotinamide (low yield) or from pyridine-3,4-dicarboxylic anhydride, using a 4-step sequence.This compound was treated with 2-lithio-5-methoxy-1-phenylsulphonylindole, affording N,N-diisopropyl-4-nicotinamide.Hydrolysis and then reduction led to 4-nicotinic acid whose amides were cyclized by phosphorus trichlorideoxide.Finally, the title compounds were obtained by Raney-nickel reduction-elimination of the 6-phenylsulphonyl protecting group.