Enantioenriched square-pyramidal oxo- and sulfidorhenium(v) complexes have been prepared and their stereochemistry studied by vibrational circular dichroism (VCD) spectroscopy.

A series of 6-(substituted oxyethyl)penem esters having the (5S) stereochemistry which are potent inhibitors of Escherichia coli leader peptidase is described. Structure-activity relationships are discussed.

fecl3.6h2o was used as an efficient catalyst for the synthesis of highly functionalized piperidines via a one-pot five-component reaction of aromatic amines, aromatic aldehydes and β-keto esters in etoh at room temperature. the remarkable advantages offered by this method are good yields, simple procedure, short reaction times, no need to column chromatography and easy work-up. the structures o...

Abstract In this paper, the synthesis of carbon skeleton cotylenin A aglycone is described. The key reactions, including an intramolecular aldol reaction, coupling and a ring-closing meta­thesis, allow for effective stereoselective access to aglycone. stereochemistry was confirmed by single-crystal X-ray crystallographic analyses related compounds.

The use of medicinal herbs as remedies reaches back to the Stone Age, and their importance a source drugs has continuously increased since then. Herbal ingredients can serve active pharmaceuticals themselves or lead substances for development synthetic with less toxicity, higher effectiveness new properties. To date, only 6% ∼600,000 plants on earth have been tested pharmacologically. Among the...

The first total synthesis of thuggacin cmc-A and the determination absolute structure are described. family antibiotics is great interest due to antibiotic activity against Mycobacterium tuberculosis. Based on assumption that seven stereogenic centers in would share same stereochemistry as thuggacin-A, all were strictly constructed a stereocontrolled manner. allowed its stereostructure be fully...

The synthesis of optically pure (R)- and (S)-2-methyl-[3,3,3-2H3] alanines of biological interest is described. The stereochemistry of the reaction of the lithio derivative of (R)-(-)-2,5-dimethoxy-3-benzyl-3-methyl-3,6-dihydropyrazine with alkyl and deuterated alkyl iodides is discussed. The configuration of the newly formed center of chirality in (R)- and (S)-2-methyl-[3,3,3-2H3] alanines is ...

The identification of four further major constituents of the pedal gland exudate of the bontebok, Damaliscus dorcas dorcas, viz. alpha-terpineol, 2-n-heptylpyridine, m-cresol and (A)-6-dodecen-4-olide and the investigation of the stereochemistry of the double bond in (Z)-6-dodecen-4-olide by means of iterative computer analysis are described. An improved synthesis of this compound is outlined.

The well-defined conformation of an N,N'-diarylurea allows a chiral sulfinyl substituent to influence diastereoselectivity in the formation of new stereogenic centres up to 14 bond lengths away.

A pair of enantioselective, ditopic macrocycles is described; the receptors bind chiral ammonium cations in a manner that depends on the stereochemistry of the cation as well as the nature of its counter anion.