178042-89-2Relevant academic research and scientific papers
Synthesis of a novel chiral 1, 3-Benzoxazinone auxiliary and its application to highly diastereoselective aldol reaction
Miyake, Tsutomu,Seki, Masahiko,Nakamura, Yoshinori,Ohmizu, Hiroshi
, p. 3129 - 3132 (1996)
Condensation of 1-menthone with salicylamide followed by isomerization of the adduct withDBU afforded a novel chiral 1, 3-benzoxazinone auxiliary, the usefulness of which was demonstrated by highly diastereoselective aldol reaction with aldehydes. Copyright
A facile synthesis of the key intermediate for penems, carbapenems, and related β-lactam antibiotics
Seki, Masahiko,Yamanaka, Takeshi,Miyake, Tsutomu,Ohmizu, Hiroshi
, p. 5565 - 5568 (2007/10/03)
Michael addition of the hydroxylamine 14 to the N-acryloyl-1,3-benzoxazinone 13 followed by the titanium enolate-mediated aldol reaction with acetaldehyde gave syn-aldol 16 in a high yield with excellent diastereoselectivity. Silylation of 16 followed by treatment with BnOLi and acetylation gave benzyl ester 19 together with the recovered chiral auxiliary 12 both in high yields. Mild hydrogenolysis of 19 furnished the β-amino acid derivative 20 which was transformed into acetoxyazetidinone 3, the key intermediate of penems 1 and carbapenems 2.
