title: Characterization of products formed by the reaction of 14C-sulphamethazinediazonium tetrafluoroborate with natural products.
abstract: 1. When bovine serum albumin (BSA) was incubated with 4-[N-(4,6-dimethyl-2-pyrimidinyl)sulphonamido] [U-14C]benzenediazonium tetrafluoroborate (14C-SDTFB) in vitro approx. half of the 14C-activity was bound (14C-BSA). Cysteine, N-ethylmaleimide, p-chloromercuribenzoate and iodoacetamide inhibited the formation of 14C-BSA. 2. When SDTFB was reacted with cysteine four major products were formed. These were identified as 3-(4-[N-(4,6-dimethyl-2-pyrimidinyl)benzenesulphonamido] diazothio)-2-aminopropionic acid (cys-SDAS), 3-(4-[4,6-dimethyl-2-pyrimidinyl) benzenesulphonamido]thio)-2-aminopropionic acid (cys-Sulmet), 4-hydroxy-N-(4,6-dimethyl-2-pyrimidinyl)benzenesulphonamide (hydroxy-Sulmet) and N-(4,6-dimethyl-2-pyrimidinyl)benzenesulphonamide (desamino-Sulmet). Diazosulphides were also formed when SDTFB was incubated with thiophenol and glutathione. 3. The diazosulphides reacted with N,N-dimethylaniline (DMA) and 2-naphthol to yield diazo compounds in 22-29% yield; when 14C-BSA was reacted with DMA under the same conditions, a diazo compound was formed-but only in 2% yield. 4. Cys-SDAS when incubated overnight (approx. 16 h) in aqueous solutions (pH 3, 5 and 8) decomposed to yield desamino-Sulmet (30-39%), hydroxy-Sulmet (13-21%), and other unidentified soluble products (24-36%); when 14C-BSA was incubated under the same conditions only 3-4% of the 14C became dissociated from BSA and only a trace amount of desamino-Sulmet was formed. 5. When 14C-SDTFB was incubated with calf thymus DNA at pH3, some of the 14C became associated with the DNA (14C-DNA). However, most of the 14C became dissociated from 14C-DNA when the latter was incubated overnight in aqueous solutions; a minor dissociation product was identified as 14C-desamino-Sulmet.
authors.affiliation: Agricultural Research Service, US Department of Agriculture, Fargo, ND 58105.
authors.forename: G D
authors.initials: GD
authors.lastname: Paulson
authors.forename: V J
authors.initials: VJ
authors.lastname: Feil
mesh_terms: D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D004247:DNA; D003979:Diazonium Compounds; D013058:Mass Spectrometry; D012710:Serum Albumin, Bovine; D013055:Spectrophotometry, Infrared; D013418:Sulfamethazine / Q000031:analogs & derivatives*; D015262:Xenobiotics
chemical_list: D003979:Diazonium Compounds; D015262:Xenobiotics; D012710:Serum Albumin, Bovine; D013418:Sulfamethazine; C063267:sulfamethazinediazonium; D004247:DNA