130516-24-4Relevant academic research and scientific papers
Lactam & amide acetals XXI. Use of pyroglutamic acid and proline in chiral synthesis of conformationally constrained piperazinones
Jain, Sanjay,Sujatha,Rama Krishna,Roy, Raja,Singh, Jujhar,Anand, Nitya
, p. 4985 - 4998 (2007/10/02)
Making use of amide activation chiral synthesis of (+)-(1S,5R)- and (-)-(1R,5S)-3,8-diazabicyclo [3.2.1]octan-2-ones (1 and 2) has been achieved from L- and D-pyroglutamates, and of (-)-(2R,6S)-, (-)-(2S,6S)-, (+)-(2s,6R)- and (+)-(2R,6R)-2-methyl-1,4-diazabicyclo[4.3.0]nonan-5-ones (3a,3b,4a and 4b) from L & D-proline methyl esters respectively. The key step of the synthesis involves a stereo-selective catalytic hydrogenation, accompanied with spontaneous cyclisation, o the nitroenamines 11, 14, 17 and 19. While this reaction was stereospecific in the case of pyro-Glu derived nitroenamines ( 11 and 14), with N-acetyl-proline derived nitroenamines (17 and 19) both 2R and 2S diastereoisomers were obtained with 40% d.e. of the diastereomer with 2-CH3 oriented cis to the 6-H. The piperazinones 1 and 2 on treatment with methanolic HCl at room temperature yielded the corresponding optically pure 5-aminomethylprolines 12 and 15 respectively.
Behaviour of 5-thioxoprolinates towards electrophiles: Synthesis of N-benzyl-2-substituted-5-thioxoprolinates
Dikshit, Dinesh K,Panday, Sharad Kumar
, p. 123 - 124 (2007/10/02)
Lithium enolate of methyl N-benzyl-5-thioxoprolinate (I) on reaction with various electrophiles gives N-benzyl-2-substituted-5-thioxoprolinates.
NEW STRATEGY FOR THE CONSTRUCTION OF CARBAPENEMS. TOTAL SYNTHESIS OF 6-epi PS-5 AND PS-5
Koskinen, Ari M. P.,Ghiaci, Mehran
, p. 3209 - 3212 (2007/10/02)
A strategically novel approach to carbapenems has been developed.The pyrrolidine ring is first constructed, appended with the required side chains, and the β-lactam ring is then annealed.We have demonstrated the utility of the approach to the asymmetric s
