What's the difference between mercaptan and sulphur?

Mercaptan


Definition:

  • (n.) Any one of series of compounds, hydrosulphides of alcohol radicals, in composition resembling the alcohols, but containing sulphur in place of oxygen, and hence called also the sulphur alcohols. In general, they are colorless liquids having a strong, repulsive, garlic odor. The name is specifically applied to ethyl mercaptan, C2H5SH. So called from its avidity for mercury, and other metals.

Example Sentences:

  • (1) Sodium dodecyl sulfate-polyacrylamide gel analyses of these cross-linked nuclear receptor complexes labeled with the covalently attaching ligand [3H]tamoxifen aziridine reveal a species of about 130,000 mol wt, while the noncross-linked or the cross-linked but mercaptan-cleaved receptor is 65,000 mol wt.
  • (2) Linear distortion of the mercaptan (polysulfide) rubber base that takes place during setting is a cause of this problem.
  • (3) Three dialysis membranes, including a polyacrilonitrile membrane, a polycarbonate membrane and a cuprophan membrane coated with charcoal, have been compared with cuprophan in order to assess their ability to clear from aqueous solution and plasma, substances thought to be of pathogenetic importance in hepatic coma (ammonia, short chain fatty acids and mercaptans), some protein bound (glycocholate and bromsulphthalein) and some middle molecular weight molecules (ethylenediaminetetracetic acid, cyanocobalamin and inulin).
  • (4) A single and chronic inhalation exposure to a complex of chemical substances being part of hydrogen sulphide-containing natural gas (hydrogen sulphide, hydrocarbon, mercaptan, sulphur dioxide) results in a decline in humoral indicators of non-specific body resistance.
  • (5) A series of alkylthiocolchcines (methyl, ethyl, n-butyl, n-hexy, n-octyl, and pinanyl) was prepared from colchicine by treatment with the appropriate alkyl mercaptan and p-toluenesulfonic acid.
  • (6) Varieties of thioalkyl-containing quinone and hydroquinone analogues of quinocarcin (1a) were prepared effectively, by addition of mercaptan to 3a-c, which were derived from 1a via DX-52-1 (1b).
  • (7) Nine of these compounds, hydrogen sulfide, methyl mercaptan, dimethyl sulfide, dimethyl disulfide, methyl acetate, ethyl acetate, heptadiene, methanol, and ethanol, were found on chicken spoiled at both 2 and 10 degrees C. xylene, benzaldehyde, and 2,3-dithiahexane were detected only in samples stored at 2 degrees C and methyl thiolacetate, 2-butanone, and ethyl propionate were associated with 10 degrees C spoilage.
  • (8) Silicone and polyether materials exhibited perceptibly less permanent deformation than mercaptan materials ten minutes after mixing.
  • (9) Nucleophilic opening of the chiral epoxide with dodecyl mercaptan gave optically active 1-S-dodecyl-3-O-trityl-1-thio-glycerol, which was used to synthesize 1-S-dodecyl-2-O-decanoyl-thio-sn-glycero-3-phosphocholine.
  • (10) To induce increased tissue levels of ammonia, mercaptans and fatty acids which are found in HE due to FHF, carefully predetermined doses of urease, dimethyldisulphide and octanoic acid were administered.
  • (11) The structures of mercaptan and sodium borohydride reaction products of neocarzinostatin chromophore A (NCS Chrom A) are compared.
  • (12) Metabolic ethyl mercaptan is sufficiently bound to be undetectable by the methods used without hydrolysis.
  • (13) This system has been shown to be capable of catalyzing the desired reactions with endogenous toxins such as phenols and mercaptans in vitro, and phenols in rabbits in vivo.
  • (14) P-site cross-linking was more sensitive to mercaptan quenching (50% at 0.5 mM) than was that at the A site (50% at greater than 2.0 mM) but both were partially shielded from solvent.
  • (15) The drug, only under acidic conditions, reacted with a stoichiometric amount of ethyl mercaptan (or beta-mercaptoethanol) to produce regio-isomers of N-sulfenylated omeprazole sulfide (5-methoxy-2[[(4-methoxy-3,5- dimethyl-2-pyridinyl)methyl]thio]-1- or 3-(ethylthio)benzimidazole).
  • (16) from L-methionine, the production of large amounts of both dimethyl disulfide and methyl mercaptan was found to be a characteristic of the genus.
  • (17) The hemolytic action of commercially available nonionic surfactants and synthesized polyoxyethylene fatty acids and mercaptans on human erythrocytes was measured.
  • (18) Running of gas-cylinder buses (GCB) fueled with liquefied propane-butane mixture added with ethyl mercaptan odorant leads to undesirable medical and social consequences.
  • (19) 2-hydroxyethyl-mercaptan an ingredient used in mammalian cell culture, inhibited antibody production in trout cells.
  • (20) 2-Cyano-6-alkylthio- and 6-phenylthiopyrazines were prepared from 2-cyano-6-chloropyrazine (CCP) in the reaction with mercaptans.

Sulphur


Definition:

  • (n.) A nonmetallic element occurring naturally in large quantities, either combined as in the sulphides (as pyrites) and sulphates (as gypsum), or native in volcanic regions, in vast beds mixed with gypsum and various earthy materials, from which it is melted out. Symbol S. Atomic weight 32. The specific gravity of ordinary octohedral sulphur is 2.05; of prismatic sulphur, 1.96.
  • (n.) Any one of numerous species of yellow or orange butterflies of the subfamily Pierinae; as, the clouded sulphur (Eurymus, / Colias, philodice), which is the common yellow butterfly of the Eastern United States.

Example Sentences:

  • (1) That suggests they are being replenished by sulphur dioxide, most probably from volcanoes.
  • (2) Sulphuric acid fluorescence is used for quantitation and specificity is achieved by the addition of tritiated oestrone to the urine hydrolysate.
  • (3) Liver scintigraphy with 67-Ga citrate and alphafetoprotein (afp) determinations in the serum were carried out in 84 patients with liver mass lesions in the preceding sulphur colloid scans.
  • (4) The use of sulphur-containing amino acids and 2-deoxyglucose in growth media led to impaired cell wall synthesis and rendered cells very susceptible to treatment with mercapto-ethanol and various lytic enzymes.
  • (5) The molecular mass (5988 Da) of the native rubredoxin has been measured by electrospray-ionization m.s., thus establishing the applicability of the technique to this type of iron-sulphur protein.
  • (6) Attention is drawn to the shortcomings in our current knowledge of the scale of turnover of the sulphur cycle and of our understanding of the microorganisms involved in specialized environments.
  • (7) N-Methylformamide extracts of acid-treated precipitated VFe protein of the V-nitrogenase of Azotobacter chroococcum are yellow-brown in colour and contain vanadium, iron and acid-labile sulphur in the approximate proportions 1:6:5.
  • (8) Here we show that a farnesyl moiety is attached to a sulphur atom of the C-terminal cysteine of T gamma-2 (active form), a part of which is additionally methyl-esterified at the alpha-carboxyl group.
  • (9) Erabutoxin a was partially hydrolysed with enzymes and sulphuric acid and the resulting peptides were separated from each other by column chromatography and paper electrophoresis.
  • (10) NADH:ubiquinone reductase, the respiratory chain complex I of mitochondria, consists of some 25 nuclear-encoded and seven mitochondrially encoded subunits, and contains as redox groups one FMN, probably one internal ubiquinone and at least four iron-sulphur clusters.
  • (11) Bacteria of the genus Thiobacillus can obtain energy from the chemolithotrophic oxidation of inorganic sulphur and its compounds (sulphide, thiosulphate and polythionates) and use this energy to support autotrophic growth on carbon dioxide.
  • (12) Bacteriophage mu2 is inactivated by both mono- and di-functional sulphur mustards at relatively low extents of alkylation.
  • (13) The study of amino acid pattern shows that sulphur containing amino acids are limiting to almost the same degree in meat and meat soy blend.
  • (14) In a case in which ovarian biopsy at laparotomy revealed typical actinomycotic "sulphur granules" and Actinomyces israelii was diagnosed, standard Actinomyces israelii cytoplasmic antigens and circulating C1-binding immune complexes were found in the patient's serum when it was tested by counterimmunoelectrophoresis.
  • (15) Experiments were performed in a cylinder full of beads open at one end and closed at the other in which a mixture of oxygen with helium or argon or sulphur hexafluoride could diffuse with ambient air through the open end.
  • (16) The results obtained indicated that both the sulphydration and trans-sulphuration pathways were operating.
  • (17) This effect may add to other factors decreasing sulphur availability in critically ill patients, and simultaneous administration of thiosulphate is therefore recommended to ensure a safe SNP treatment during and after coronary bypass operations.
  • (18) (4) There is no specific therapy for poisoning by sulphur mustard.
  • (19) Among various acetylated proteins, proteins insoluble in 0.1m-sulphuric acid have the highest radioactivity.
  • (20) Desulfovibrio africanus ferredoxin III is a monomeric protein (Mr 6585) containing seven cysteine residues and 7-8 iron atoms and 6-8 atoms of acid-labile sulphur.

Words possibly related to "mercaptan"