(n.) Olefiant gas, or ethylene; hence, by extension, any one of the series of unsaturated hydrocarbons of which ethylene is a type. See Ethylene.
Example Sentences:
(1) This can be interpreted as the result of polarizing inductive (I-) and mesomeric (M-) effects exerted by Cl- as well as by CH3-substituents on the olefinic double bond.
(2) The following trans compounds were synthesized and their IC50 values were measured: homologated trans-isomers with one methylene chain (47 and 53), an olefin derivative (58), and optically active derivatives [-)-11 and (+)-23).
(3) The combined rate of formation of anomalous alcoholic and olefinic products was 10% the Vmax determined for the conversion of 1 to 2.
(4) These results would indicate that incorporation of a reactive olefinic compound to a lipidic microphase does not provide "per se" an efficient protection towards its attack by ozone.
(5) These changes were correlated to the decrease of the ratio of saturated to olefinic fatty acids in the mycelium, suggesting that alcohols and other polar lipophilic compounds can interfere with the biosynthesis and the function of the cytoplasmic membrane in Streptomyces.
(6) 108, 3837-3838), suggesting that the mechanism of epoxidation of olefins by methane monooxygenase differs at least in part from that of cytochrome P-450.
(7) Patchoulol synthase copurified with the ability to transform farnesyl pyrophosphate to cyclic olefins (alpha- and beta-patchoulene, alpha-bulnesene, and alpha-guiaene) and this observation, plus evidence based on differential inhibition and inactivation studies, suggested that these structurally related products are synthesized by the same cyclase enzyme.
(8) Oxidation of VI to the 24-aldehyde VII, followed by Wittig olefination with isopropyltriphenylphosphonium iodide gave 3 beta-acetoxy-5 alpha-cholesta-8(14),24-dien-15-one (VIII), which was hydrolyzed to the free sterol IX.
(9) The starting olefins were coated on a variety of solid substrates, exposed to known ozone concentrations and then analyzed for the corresponding aldehyde with a gas chromatograph equipped with a flame-ionization detector.
(10) This new analog (CD270), which contains no olefinic double bonds, is characterized by its chemical stability to light and atmospheric oxidation.
(11) This approach, used in conjunction with tandem mass spectrometry, allows the determination of olefinic bond location.
(12) The unexpected inactivity of 1f (E = C6H4-p-NO2) as a Michael acceptor and its very powerful competitive inhibition of papain were rationalized by molecular graphics which showed the nitrophenyl moiety rotated out of conjugation with the olefin and interacting instead with the hydrophobic S1' region of papain.
(13) Detection is based on the mass increase accompanying replacement of ethylene by other gas-phase olefins to form the corresponding olefin-substituted products.
(14) With cyclase II, the doubly labeled substrate gave bicyclic olefins with 3H:14C ratios of from 13 to 20, indicating preferential, but not exclusive, utilization of the (3S)-enantiomer in this case.
(15) That is, arene.Cr(CO)3 complex-catalyzed 1,4-hydrogenation of the dienes 13 and 58, obtainable from the Corey lactone in good yields, under high H2 pressure afforded the exocyclic olefins 14 and 61 stereospecifically in excellent yields, and these intermediates were converted to therapeutically useful carbacyclin (2) and its analogs 3-7 in a usual way.
(16) Resonance lines of the olefinic, methylene, methyl and carboxyl carbon nuclei are sufficiently characteristic to permit unequivocal designation of double bond position for each isomer.
(17) These deal with: (a) reactive properties of nucleic acids, including their component bases; (b) biological recognition processes, including drug-receptors and enzyme-substrate interactions; and (c) chemical carcinogenesis, referring specifically to the polycyclic aromatic hydrocarbons and halogenated olefins and their epoxides.
(18) For olefins an initial electron transfer to oxidized haemprotein gives a substrate cation radical.
(19) The structure of the adduct was determined by 1H-NMR spectrometry, showing that thiolate attacked the olefinic double bond of the antibiotic.
(20) A series of lysophosphatidylethanolamine analogs containing saturated and methylene-interrupted cis-olefinic fatty chains was synthesized by phosphorylation and phosphonylation of respective fatty alcohols.