(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.
Thiophene
Definition:
(n.) A sulphur hydrocarbon, C4H4S, analogous to furfuran and benzene, and acting as the base of a large number of substances which closely resemble the corresponding aromatic derivatives.
Example Sentences:
(1) Quantitative structure activity relationships of 2-amino-3-carboxylic acid ethyl ester thiophene derivatives are described.
(2) Some of the thiophenes and their acetylenic derivatives possess extremely potent phototoxic activities toward membrane-containing viruses.
(3) The compounds were obtained by condensation of appropriate hydrazines with thiophene 2-carboxaldehyde (series 1), thiophene 3-carboxaldehyde (series 2), and 5-nitrothiophene-2-carboxaldehyde (series 3).
(4) The prototype kappa-selective agonist, PD117302 (trans-N-methyl-N-[2-(1-pyrrolidinyl)cyclohexyl]benzo[b]thiophene-4- acetamide, 2) has been regio- and stereoselectively substituted in the C-4 and C-5 positions of the cyclohexyl ring with the methyl ether and spiro tetrahydrofuran groups.
(5) Since no previously identified genes involved in thiophene metabolism are located in this region, we designated the gene for the 48-kDa protein as thdF.
(6) Among the compounds described are 6-hydroxybenzo[b]thiophene-2-sulfonamide (16) and its acetate ester (23), which are among the most potent ocular hypotensive agents in this class, as assessed in the alpha-chymotrypsinized rabbit.
(7) The normalizing effects of the thiophene compounds on serum phosphorus levels were not significant at the dosages used.
(8) Maximum photo-basophil-histamine-release was 4% with acetylsalicylic acid, 10% with benoxaprofen, 20% with thiophene, 28% with diclofenac, 39% with tiaprofenic acid, 40% with carprofen, 55% with ketoprofen, and not demonstrable with indoprofen.
(9) The more hydrophobic cephalosporins, with a thiophene moiety at the C7 position, were more active than C7-methoxyiminoaminothiazole derivatives against S. aureus H (beta-lactam-susceptible), and compounds with a thioether function at C3 were more active than those with a sulphonyl function at this position.
(10) Several guanidine compounds were synthesized by the reaction of acid chlorides of thiophene and furan with guanidines.
(11) Alpha-terthienyl (alpha-T), a phototoxic thiophene compound isolated from marigolds (Tagetes species), affects cell membranes and does not appear to induce cytogenetic damage.
(12) In a directed search for the best compounds for clinical evaluation, some 150 selected nitroaromatic compounds, representing 6 distinct types, namely, furans, thiophenes, imidazoles, pyrazoles, pyrroles, and triazoles, have been synthesized and tested as hypoxic cell radiosensitisers and bioreductive drugs.
(13) Replacement of ring A by heterocyclic rings (thiophene or pyridine) leads to analogues with only moderate activity.
(14) These results clearly show that all three thiophene systems have potent activity as antihypertensive agents and that 3 and 4 are more potent than 1 or 2 as alpha 1-antagonists in vivo.
(15) A comparative study of the intestinal transport of DL-tryptophan and its 1-methylindole (tryptophan-l-Me) and benzo[b]thiophene (tryptophan-S) analogs has been carried out in vitro, using the everted intestinal sac of the rat and hamster.
(16) Except for cardioselectivity at low doses, the thiophenic analogue of metoprolol behaves in a very similar way as this compound in all the aspects considered in a preliminary pharmacological study.
(17) Six-month chronic oral toxicity studies of 7-chloro-3-[1-(2, 4-dichlorophenyl)-2-(1H-imidazol-1-yl)ethoxy-methyl] benzo[b]thiophene (sertaconazole, FI-7045, CAS 99592-32-2) were carried out in rats and ferrets.
(18) N-(3-dimethylaminopropyl)naphtho[2,1-b]thiophene-4-carboxamide and the 6-substituted methoxy, methyl, fluoro, chloro, bromo, trifluoromethyl, and cyano derivatives have been shown to bind to DNA via intercalation with binding constants in the 35-900 X 10(3) range at 25 degrees C, pH 7, and [Na+] = 0.019M.
(19) Tienilic acid (TA) is metabolized by human liver microsomes in the presence of NADPH with the major formation of 5-hydroxytienilic acid (5-OHTA) which is derived from the hydroxylation of the thiophene ring of TA.
(20) The synthesis of 1-substituted benzothieno[2,3-d]imidazoles and their most suitable synthesis precursor 2-nitro-3-substituted-amino benzo[b]thiophenes is reported.