Showing papers by "Stephen Hanessian published in 1992"
59 citations
TL;DR: In this paper, a one-step deoxygenation of 2-hydroxylactones or their acetates using samarium diiodide as an electron-transfer reagent in conjunction with a proton source is described.
55 citations
TL;DR: In this article, the treatment of alkyl cyclohexanones with topologically unique bicyclic phosphonamides derived from the C 2 symmetric (R,R )- and (S,S )-N,N′-dimethyl 1,2-trans -cyclohexane diamine leads to enantiomerically pure allylidene and benzyl-idene alkyylcyclo-hexanes.
53 citations
TL;DR: In this article, enantiomerically pure alkyl cyclohexane ethylidene derivatives with 2,3-di-O-benzyl D-and L-glyceraldehyde and related aldehydes in the presence of Lewis acids are treated.
24 citations
20 citations
TL;DR: The photo-initiated fragmentation of 2-azetidinone-4-car ∆-ylic acid-2-thiopyridylhydroxamates (Barton reaction) in the presence of Michael acceptors leads to the introduction of a doubly functionalized carbon chain, useful for the elaboration of carbapenem and related β-lactam antibiotics as mentioned in this paper.
19 citations
18 citations
18 citations
TL;DR: In this paper, the optimal structures of N-acetylmuramyl-L-alanyl-D-isoglutamine (MDP) and its analog, N -acetylmuramyl -L-Alanyl-3-carbomethoxymethyl-Dproline methyl ester (MAP) in DMSO have been investigated by one-and two-dimensional 1H NMR spectroscopy.
9 citations
TL;DR: The stereochemical preferences observed were dictated by the nature of vicinal and remotely placed substituents in the lactone as discussed by the authors, and the stereochemical preference observed were dependent on the type of substitutions.
7 citations
TL;DR: In this paper, a liaison hydrogene intramoleculaire relieves le groupe phosphoryl au groupe hydroxyle, qui retreint la conformation.
Abstract: C 22 H 35 N 2 O 2 P cristallise dans P2 1 avec a=9.101, b=8.612, c=13.790A, β=92.29°, Z=2; affinement jusqu'a R=0.031. Dans ce compose, l'alcool tertiaire est dans une position axiale et le groupe 2-methyl est dans une position equatoriale. Une liaison hydrogene intramoleculaire relie le groupe phosphoryl au groupe hydroxyle, qui retreint la conformation.
TL;DR: In this article, a composition of cyclohexane attache a un groupe phosphoryl de coordination tetraedrique is presented, which is composed of a cyclophenylmethyl attache and a phenylmethyl de configuration.
Abstract: Cristallisation dans P2 1 2 1 2 1 avec a=10.636, b=12.759, c=18.185A, Z=4; affinement jusqu'a R=0.039. Ce compose est constitue d'un cyclohexane attache a un groupe phosphoryl de coordination tetraedrique. Un groupe phenylmethyl de configuration R ponte l'atome P et le cycle cyclohexanol. L'alcool tertiaire est dans une position axiale et le 4-t-butyl est dans une position equatoriale
TL;DR: In this article, a comparative study was made of chiral nonracemic γ-alkoxy and γureido-α,β-unsaturated esters with lithium dimethylcuprate in the presence of trimethylsilyl chloride.
Abstract: A comparative study was made of the reaction of chiral nonracemic γ-alkoxy and γ-ureido-α,β-unsaturated esters with lithium dimethylcuprate in the presence of trimethylsilyl chloride. The possible origins of the anti- and syn-additions respectively are discussed and rationalized
TL;DR: In this article, a composition of cyclohexane attache a un groupe phosphoryl de coordination tetraedrique is presented, which is composed of a cyclophenylmethyl attache and a phenylmethyl de configuration.
Abstract: Cristallisation dans P2 1 2 1 2 1 avec a=10.636, b=12.759, c=18.185A, Z=4; affinement jusqu'a R=0.039. Ce compose est constitue d'un cyclohexane attache a un groupe phosphoryl de coordination tetraedrique. Un groupe phenylmethyl de configuration R ponte l'atome P et le cycle cyclohexanol. L'alcool tertiaire est dans une position axiale et le 4-t-butyl est dans une position equatoriale
TL;DR: In this article, a liaison hydrogene intramoleculaire relieves le groupe phosphoryl au groupe hydroxyle, qui retreint la conformation.
Abstract: C 22 H 35 N 2 O 2 P cristallise dans P2 1 avec a=9.101, b=8.612, c=13.790A, β=92.29°, Z=2; affinement jusqu'a R=0.031. Dans ce compose, l'alcool tertiaire est dans une position axiale et le groupe 2-methyl est dans une position equatoriale. Une liaison hydrogene intramoleculaire relie le groupe phosphoryl au groupe hydroxyle, qui retreint la conformation.