Ribose conversion with amino acids into pyrraline platform chemicals – expeditious synthesis of diverse pyrrole-fused alkaloid compounds

Abstract

One-pot conversion of sustainable d-ribose with l-amino acid, methyl esters produced pyrrole-2-carbaldehydes 5 in reasonable yields (32–63%) under pressurized conditions of 2.5 atm at 80 °C.

Recent synthetic journey on pyrrole-fused compounds

“…This strategy Scheme 11 One-pot synthesis of pyrrolo-piperazinones from naturally occurring D-ribose. 26 was generalized with N-benzylated pyrroles and o-bromomethoxyphenyl to form a rare N-bridge pentacyclic derivative and in all cases, we obtained moderate to good yield. We proposed a general mechanistic pathway for heteroarylation, which proceeded via oxidative addition, followed by intramolecular C-H activation in the presence of Pd-catalyst.…”

“…Moreover, 42c and 42d showed high anti-inflammatory properties. 26 This is the extension of the work on the aldohexose system and the yield of the fused product is not good enough. Thus, further study is needed with different acid catalysts and solvents for the improvement of the desired product.…”

The quantitative pyrrole protection of l-phenylalanine/l-phenylalaninol in aqueous media and rationally updating the mechanisms of the Clauson-Kaas reaction through DFT study

“… 17 The one-pot conversion of sustainable d -ribose with l -amino acid methyl esters produced pyrrole-2-carbaldehydes in reasonable yields under pressurized conditions with the assistance of oxalic acid in DMSO. 18 Although malonic acid was still adopted as the necessary catalyst, the amadori compound N -(1-deoxy- d -fructos-1-yl)- l -proline exhibits exemplarily much higher isomerization rates than d -fructose through the C-1 substituent-mediated intramolecular catalytic effect. 19 The intrinsic origin of C/N-ribonucleoside through the reaction of 2,4,6-triaminopyrimidine (TAP) with d -ribose in aqueous solution was understood by employing detailed density functional theory (DFT) studies.…”