Acrolein is the metabolite of cyclophosphamide (CP) believed to be involved in the bladder toxicity associated with this anticancer drug. The mechanism by which this extremely reactive intermediate is delivered to the bladder is not known. Glutathione (GSH) readily conjugates with acrolein, and the acrolein mercapturate S-(3-hydroxypropyl)-N-acetylcysteine (3-hydroxy-PrMCA) has been found in the urine of animals and man given CP. The objectives of this study were to prepare and characterize synthetic standards of the GSH acrolein adduct (3-oxopropyl)glutathione (3-oxoPrGSH), the acrolein mercapturates S-(3-oxopropyl)-N-acetylcysteine (3-oxoPrMCA) and 3-hydroxyPrMCA, and the S-oxidation product of 3-oxoPrMCA (3-oxoPrMCA S-oxide). In addition, the release of acrolein from, and the bladder toxicity of, these conjugates was determined. 3-OxoPrGSH and 3-oxoPrMCA were prepared with a 99% yield by condensing acrolein with GSH and N-acetylcysteine, respectively. 3-HydroxyPrMCA was prepared with a 63% yield by refluxing 3-chloropropanol and N-acetylcysteine in a basic medium. Oxidation of 3-oxoPrMCA with H2O2 was used to prepare 3-oxoPrMCA S-oxide. By decreasing the reaction time to 1 h, and adjusting the ratio of 3-oxoPrMCA to H2O2, the yield of 3-oxoPrMCA S-oxide was increased to 96%. The anhydrous aldehyde, 3-oxoPrMCA, afforded characteristic aldehydic proton resonances (1H NMR) in deuterated dimethyl sulfoxide. New resonances were observed in deuterated water, indicating a 75% hydration of the aldehyde to the corresponding geminal diol. This phenomenon was enhanced with 3-oxoPrMCA S-oxide where approximately 100% hydration of the aldehyde to the corresponding geminal diol was observed. When incubated at 25 degrees C in 100 mM potassium phosphate buffer containing 1 M KCl, pH 8.0, 3-oxoPrMCA released approximately 6% and 3-oxoPrMCA S-oxide released approximately 16-18% of the theoretical maximum yield of acrolein after 30 min, as indicated by an increase in absorbance at 210 nm and confirmed by trapping this aldehyde as a semicarbazone. There was less than a 2% yield of acrolein from 3-hydroxyPrMCA or 3-oxoPrGSH under similar conditions. At pH 7.4 the release of acrolein from 3-oxoPrMCA and 3-oxoPrMCA S-oxide was decreased by 50%. An assay where aldehydes are reacted with m-aminophenol in acid media produced fluorescence consistent with 72%, 46%, 23%, and 1% yields of acrolein from 3-oxoPrMCA S-oxide, 3-oxoPrMCA, 3-oxoPrGSH, and 3-hydroxyPrMCA, respectively.(ABSTRACT TRUNCATED AT 400 WORDS)

Bacillomycin Lc, a newantifungal antibiotic of the iturin class, was isolated from a strain of Bacillus subtilis as a set of five congeners. The structure as determined by chemical and spectrometric analyses has been shown to differ from that of bacillomycin L by sequence changes from aspartate-1 to asparagine-1 and from glutamine-5 to glutamate-5. The five congeners differ from each other only in the structure of the aliphatic side chain of the constituent /?-amino acid. The hydrophobicity of the /?-amino acid affects the antifungal activity of the congener, as activity increased in the order of increased congener retention on a reversed-phase HPLCcolumn.Iturins are antifungal antibiotics produced by Bacillus subtilis that are characterized by a cyclic peptidolipid structure consisting of eight amino acids. Their common structure consists of a macrocycle of seven a-amino acids in a LDDLLDL configuration sequence, closed by a /?-amino acid linkage. 1}During a screening of tree xylem for microorganisms with biological control potential against tree phytopathogens, several Bacillus species were isolated displaying in vitro activity against Ophiostoma ulmi (Buisman) Nannf., the Dutch elm disease fungus.2) Amongthese, Bacillus subtilis isolate FS94-14 showed the greatest activity, prompting this study to characterize the antifungal compoundsproduced by this organism.

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