ABSTRACT
The synthesis of 5-amino-5-deoxy-1,2-O-(S)-trichloroethylidene-beta-L-arabinofuranose and 6-amino-6-deoxy-1,2-O-(S)-trichloroethylidene-alpha-D-glucofuranose is described by a simple three- or four-step route. Antibacterial potency of the new compounds was determined using an inhibition zone diameter test. The results show that these compounds have a broad-spectrum activity against Gram-positive, Gram-negative bacteria and Candida albicans.
Subject(s)
Amino Sugars/chemical synthesis , Amino Sugars/pharmacology , Anti-Infective Agents/chemical synthesis , Anti-Infective Agents/pharmacology , Chloralose/analogs & derivatives , Amino Sugars/chemistry , Anti-Infective Agents/chemistry , Bacteria/drug effects , Fungi/drug effects , Microbial Sensitivity Tests , StereoisomerismABSTRACT
Sunlight-mediated photooxygenation of 3-O-acetyl and 3-O-methyl derivatives of 1,2-O-alkylidene-5(E)-eno-5,6,8-trideoxy-alpha-D-xylo-oct-1,4-furano-7-uloses (1a-e) in carbon tetrachloride solution gave stable 4,7-epidioxy derivatives in 4R (2a-e) and 4S (3a-e) configurations. The presence of an endo alkyl, on the 1,2-O-alkylidene group and its size, resulted in an increase of the yield of the 4S isomers. 3-O-acetyl derivatives yielded products as a mixture of C-7 anomers, whereas 3-O-methyl derivatives gave pure single stereoisomers.
Subject(s)
Deoxy Sugars/chemical synthesis , Peroxides/chemical synthesis , Spiro Compounds/chemical synthesis , Sunlight , Deoxy Sugars/chemistry , Deoxy Sugars/radiation effects , Magnetic Resonance Spectroscopy , Models, Molecular , Oxidation-Reduction , Peroxides/chemistry , Peroxides/radiation effects , Photochemistry , Spectrometry, Mass, Electrospray Ionization , Spiro Compounds/chemistry , Spiro Compounds/radiation effectsABSTRACT
The West Anatolian Region is one of the most important areas for industrialization, population density and traffic in Turkey. Therefore, the leaves of Populus nigra L. (Salicaceae), which are used as biomonitor to investigate the levels of the trace elements Cd, Pb, Fe, Zn and Cu, were sampled at 30 locations having different pollution levels in the region. The concentrations of elements were determined by atomic absorption spectrometry. The samples were collected at both reference and contaminated locations where iron was found as the priority element. The strong association between a gradient of contamination and concentration in all samples tested indicates that they are reflecting well the environmental changes, and that they appear as appropriate biological indicators of heavy metal contamination.
Subject(s)
Environmental Monitoring/statistics & numerical data , Environmental Pollutants/analysis , Metals, Heavy/analysis , Plant Leaves/chemistry , Populus , Spectrophotometry, Atomic , TurkeyABSTRACT
The preparation of 3,5-(E)-dieno-3,5,6,8-tetradeoxy-(S)-1,2-O-trichloroethylidene-alpha-D-glycero-octo-1,4-furano-7-ulose starting from either 1,2-O-(S)-trichloroethylidene-alpha-D-glucofuranose (beta-chloralose) or 1,2-O-(S)-trichloroethylidene-alpha-D-galactofuranose (galactochloralose) and the preparation of methyl 3,5-(E)-dieno-3,5,6-trideoxy-(S)-1,2-O-trichloroethylidene-alpha-D-glycero-hepta-1,4-furano-uronate starting from beta-chloralose are described. Endocyclic double bond formations were realised by the elimination of 3-acetoxy groups using DMF-sodium bicarbonate. This elimination was not successful when the starting compound was 1,2-O-(R)-trichloroethylidene-alpha-D-glucofuranose (alpha-chloralose), where the trichloromethyl group occupies the endo position.
