Reference

Structural requirements for preventing the aspirin- and the arachidonate-induced inactivation of platelet cyclo-oxygenase: additional evidence for distinct enzymic sites

Structural requirements for preventing the aspirin- and the arachidonate-induced inactivation of platelet cyclo-oxygenase: additional evidence for distinct enzymic sites. Rotilio, Domenico; Joseph, Danielle; Hatmi, Mohammed; Vargaftig, B. Boris (Dep. Physiopathol. Exp., Inst. Pasteur, Paris 75015, Fr.). Eur. J. Pharmacol., 97(3-4), 197-208 (English) 1984. CODEN: EJPHAZ. ISSN: 0014-2999. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) 2-Hydroxybenzoic acid (salicylic acid) [69-72-7] prevents the inhibition by aspirin (ASA) [50-78-2] of platelet aggregation and of the generation of thromboxane A2 [57576-52-0] from arachidonic acid (AA) [506-32-1]. The ability of 2-hydroxybenzoic acid analogs to block the action of ASA and to prevent the platelet desensitization due to a 1st exposure to AA was studied.Several substances with their cas registry numbers 303-07-1 and 65-85-0 may be metioned in this study. Inactivation was prevented when exposure to AA was done in the presence of reversible inhibitors of cyclooxygenase [39391-18-9]. PhOH [108-95-2], Me salicylate [119-36-8] and L8027 [36504-64-0] were thus strong inhibitors of AA-induced platelet activation and desensitization. The minimal structural requirement for inhibition of thromboxane A2 generation from AA was a phenolic OH group, as benzoic acid [65-85-0] was fully inactive. 2-Hydroxybenzoic acid and, to some extent, 2,6-dihydroxybenzoic acid [303-07-1] were effective against ASA, the most active substances being Me salicylate and L8027. 2-Methoxybenzoic acid [579-75-9] was devoid of activity, which highlights the fact that an OH group must be available. This work favors the hypothesis that nonsteroidal anti-inflammatory drugs react with 2 sites of cyclooxygenase, which were named the supplementary and the catalytic sites. The interaction of 2-hydroxybenzoic acid and of its analogs with the supplementary site is necessary but not sufficient for the efficacy of these compds. as cyclooxygenase inhibitors. The degree of interaction with the supplementary site and the modification of the catalytic site det. the potency of these compds. as cyclooxygenase inhibitors. For preventing ASA inactivation, an interaction with the supplementary sites is always necessary, but furthermore an appropriate group, preferentially in the position ortho to the OH, is needed. .

Effect of clonal specificity of the monoterpene alcohol composition of tea shoots on black tea aroma profile

Effect of clonal specificity of the monoterpene alcohol composition of tea shoots on black tea aroma profile. Takeo, Tadakazu (Tea Technol. Div., Natl. Res. Inst. Tea, Shizuoka 428, Japan). JARQ, 17(2), 120-4 (English) 1983. CODEN: JARJA9. ISSN: 0368-1297. DOCUMENT TYPE: Journal CA Section: 17 (Food and Feed Chemistry) Two tea varieties, Camellia sinensis and C. sinensis assamica, had different aromas, and this difference was attributed in part to different linalool [78-70-6] and geraniol [106-24-1] contents. The terpene index (linalool/linalool + geraniol) was very high (~1.00) in most assamica clones from India, Sri Lanka, and Malaysia, whereas Japanese black tea clones of a hybrid of the 2 species had terpene indexes of 0.25-0.75. Green tea clones of C. sinensis from Japan had indexes of 0.25-0.70, whereas Chinese C. sinensis had more geraniol in the pentane-sol. volatiles: terpene indexes 0.05-0.90. Aroma conc. from black tea contained mainly geraniol and linalool, but also contained cis-3-hexenol [928-96-1], methylsalicylate [119-36-8], 2-phenylethanol [60-12-8], cis-2-penten-1-ol [1576-95-0], benzyl alc. [100-51-6], 1-penten-3-ol [616-25-1], trans-2-hexenol [928-95-0], hexanol [111-27-3], trans-2-hexenylformate [53398-78-0], linalool oxide furanoid-cis [5989-33-3], linalool oxide furanoid-trans [34995-77-2], benzaldehyde [100-52-7], trans-3, trans-5-octadien-3-ol [88898-99-1], cis-3-hexenylhexanoate [31501-11-8], linalool oxide pyranoid-trans [39028-58-5], b-ionone [79-77-6], cis-jasmone [488-10-8], and nerolidole [142-50-7]. Mech. injured tea shoots contained less linalool and geraniol than intact shoots.Except for chemicals metioned above, 928-95-0 and 488-10-8 are also used. .