These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Enantioselective autocatalysis. III. Configurational and conformational studies on a 1,4-benzodiazepinooxazole derivative.
    Author: Miller BL, Bonner WA.
    Journal: Orig Life Evol Biosph; 1995 Dec; 25(6):539-47. PubMed ID: 11536711.
    Abstract:
    We report here on configurational and conformational studies undertaken on the bromofluoro-1,4-benzodiazepinooxazole derivative I, which has previously been found capable of undergoing total spontaneous resolution under racemizing conditions. Due to its bridgehead N-atom I may exist in any of four diastereomeric forms, CRNR (or CSNS) and CRNS (or CSNR). Molecular mechanics calculations revealed that in their lowest energy conformations the CRNR (or CSNS) diastereomers were favored over the CRNS (or CSNR) diastereomers by some 3.42 kcal/mol, while semi-empirical quantum mechanical calculations indicated heats of formation also favoring the CRNR (or CSNS) diastereomers by 3.83 kcal/mol. The 1H NMR spectra of the three crystalline modifications (alpha, beta and gamma) of I were examined in acetone, and found to be identical. These data, combined with the results of the above calculations, suggest that I exists in methanol or methanol-acetone solutions as the CRNR (or CSNS) enantiomer prior to its racemization.
    [Abstract] [Full Text] [Related] [New Search]