Enantioselective Deprotonative Ring Contraction of N1-Methyl-N4-Boc-benzo[e][1,4]diazepine-2,5-diones
摘要:
N1-Methyl-N4-Boc-benzo[e][1,4] diazepine 2,5-diones were prepared in good yield an high stereo chemical purity from five amino acids Upon deprotonation these compounds undergo ring contraction to the corresponding quinolone 2,4-diones withhigh enantioselectivity, providing efficient entry to a potentially useful drug scaffold Mechanistic commentary and comparisons to related reactions are provided.
1,4-benzodiazepin-2,5-diones have been synthesized in good overall yields by two routes, the first one by cyclisation of dipeptides prepared from Boc anthranilic acid and alpha-amino acid methyl esters, the second one by reaction of N-carboxy alpha-amino acid anhydrides with Boc anthranilic acid.