1,720,971 research outputs found
Cyclopentaannulation Reactions between Nitrocycloalkenes and Diacetyl Morpholino Enamine
No full textSynthesis of a val-pro diaminodiol dipeptide isostere by epoxyamine cyclization
No full textThe base-catalyzed hydroazidation of alpha'-amino alpha,beta-unsaturated ketones with in situ generated hydrazoic acid was found to proceed with highstereoselectivity in favor of the syn product. The stereoselectivity is controlled by the configuration of the enone and syn/anti ratios up to 7:1were obtained with secondary and tertiary amines at low temperature. By this route the diamino alcohol core of HIV-PR inhibitors ritonavir andlopinavir was synthesized in 37% yield from phenylalanine
Synthesis, Characterization, and Solution Behavior of Optically Active cis beta Organocobalt Salen_Complexes with L-Amino Acids.
No full textThe reaction of a cis â folded organocobalt derivative with a salen-type ligand, 1, isolated as racemic compound of ¢ and ¤ enantiomers, with enantiomerically pure R-L amino acids is reported. The reaction between racemic 1 and L-tyrosine afforded a mixture of the two diastereoisomers ¢-2 and ¤-2, which could be separated by fractional crystallization owing to the lower solubility of ¢-2. The absolute configuration of the two diastereomers was unequivocally assigned from the X-ray structure, using the known absolute configuration of the asymmetric carbon of the amino acid as internal reference. The reaction of racemic 1 with trans-4-hydroxy-L-proline afforded only the diastereoisomer with a ¢ configuration of the tetradentate ligand, as proved by X-ray diffractometric analysis
A Guest-Induced Assembly of a Molecular Box from Methylcobaloxime and 1,4-Phenylenbisboronic acid.
No full textSelf Assembly of Cobaloximes and Rhodoximes with 3-Aminophenylboronic Acid: A Molecular Triangle and a Polymer.
No full textAlternative cocrystallization of ‘‘almost ’’enantiomers and true enantiomers in some cis -beta organocobalt salen-type complexes with a amino acids.
No full textNew Alkyl-Cobalt(III) Complexes with Tridentate Amino-Oxime Ligands: Synthesis, Structure, and Reactivity.
No full textEUR. J. INORG. CHE
Reduction Chemistry of Fe_2(NO)_4(\mu-PPh_2)_2 and Selective Synthesis of Isomeric Doubly Bridged Methylene Tetraphenylbiphosphine and Diphenylphosphido- Methylenediphenylphosphine Complexes
No full text1-Arylsulfonylamino-1,2,3-triazole derivatives from functionalized 1,2-cyclohexandiones
No full textThe heterocyclization reaction of arylsulfonylhydrazones from alkyl substituted 1,2-cyclohexanediones is sensitive to the steric requirements of the alkyl groups. A mechanism for the cyclization in acidic medium is also reported
Synthesis and Characterization of Isomeric Binuclear Double- Bridged Alkylidene Tetraphenyldiphosphine and Diphenylphosphido Methylenediphenylphosphine Iron Nitrosyl Complexes
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