ABSTRACT
109 patients (62 boys/men and 47 girls/women) suffering from bronchial asthma induced by pollen allergens were typed for HLA-DRB1 and -DQBl alleles, respectively, by a low resolution SSP technique. Frequencies of DRB1 alleles varied from 0.5 % to 16.1â %. The most frequent was HLA-DRB1*11 (16.1â %), the least frequent HLA-DRB1*09 (0.4â %). Occurrence rates of HLA-DQB1 alleles ranged from 2.3â % to 37.2â %, HLA-DQB1*03 being the most frequent (37.2â %) and DQB1*04 stood on the opposite pole (2.3â %). By comparing to occurrence rates in the healthy population, no statistically significant differences were disclosed (Tab. 2, Ref. 16).
Subject(s)
Asthma/genetics , HLA-DQ beta-Chains/analysis , HLA-DRB1 Chains/analysis , Adolescent , Adult , Asthma/immunology , Child , Female , Gene Frequency , Humans , Male , Middle Aged , Slovakia , Young AdultABSTRACT
Stereochemical studies of a cruciferous oxindole phytoalexin, (S)-(-)-spirobrassinin [(-)-4], and its oxazoline analogue, spirooxazoline (11), were carried out. Racemic spirobrassinin [(+/-)-4] was synthesized by SOCl(2)- or MsCl-mediated cyclization of dioxibrassinin [(+/-)-8]. Treatment of (3-hydroxyoxindol-3-yl)methylammonium chloride [(+/-)-9] with CSCl(2) and subsequent methylation of the obtained spirooxazolidinethione (+/-)-10 afforded spirooxazoline [(+/-)-11]. Enantioresolution of (+/-)-4 and (+/-)-11 was achieved by derivatization with (S)-(-)-1-phenylethyl isocyanate (12), chromatographic separation of diastereomeric amides 13, 14 or 15, 16, and their cleavage with CH(3)ONa. Absolute configuration of the stereogenic center in natural (S)-(-)-4 was derived from the exciton, calculated via CD methods, and unequivocally confirmed by X-ray crystallographic analyses of 1-[1'S,4'R-(-)-camphanoyl] derivatives [(-)-19 and (-)-20] of (+)- and (-)-4. Novel enantiomeric enrichment phenomena of 4 and 11 were discovered during their chromatographic separations under achiral HPLC conditions. Screening of antifungal activity against the fungus Bipolaris leersiae revealed no significant dependence of this activity on absolute configuration.
Subject(s)
Antifungal Agents/chemical synthesis , Brassicaceae/chemistry , Spiro Compounds/chemical synthesis , Thiazoles/chemical synthesis , Antifungal Agents/chemistry , Antifungal Agents/pharmacology , Ascomycota/drug effects , Circular Dichroism , Crystallography, X-Ray , Microbial Sensitivity Tests , Molecular Conformation , Oxazoles/chemical synthesis , Oxazoles/chemistry , Spectrophotometry, Ultraviolet , Spiro Compounds/chemistry , Spiro Compounds/pharmacology , Stereoisomerism , Thiazoles/chemistry , Thiazoles/pharmacologyABSTRACT
Enantiomeric purity of a cruciferous phytoalexin, spirobrassinin (1), was determined by chiral HPLC analysis. The enantiomeric excesses of two natural spirobrassinin fractions separated by nonchiral chromatography were considerably different. A significant enantiomeric enrichment was observed during the nonchiral chromatographic separation of an artificial enantiomeric mixture of 1.
