Reference

Gas chromatography-mass spectrometric analysis of oxidative degradation products of sporopollenin in Magnolia grandiflora (Magnoliaceae) and Hibiscus syriacus (Malvaceae)

Gas chromatography-mass spectrometric analysis of oxidative degradation products of sporopollenin in Magnolia grandiflora (Magnoliaceae) and Hibiscus syriacus (Malvaceae). Kawase, Masaya; Takahashi, Masamichi (Faculty Education, Kagawa University, Takamatsu 760, Japan). Journal of Plant Research, 109(1095), 297-299 (English) 1996 Botanical Society of Japan. There are some commonly used reagents like 38147-00-1 in this article. CODEN: JPLREA. ISSN: 0918-9440. DOCUMENT TYPE: Journal CA Section: 9 (Biochemical Methods) Section cross-reference(s): 11 Sporopollenin can be dissolved in water by oxidative degrdn. using KMnO4. In mature pollen grains of M. grandiflora and H. syriacus, some org. compds. were extd. from the aq. phase into hexane and analyzed by gas chromatog.-mass spectrometry (GC-MS). The anal. shows that the extd. compds. include some organosilicon compds. By searching the mass spectra database, the organosilicon compds. are suggested to be 1,1,1,5,7,7,7-heptamethyl-3,3-bis(trimethylsiloxy)tetrasiloxane and 1,1,1,3,5,7,7,7-octamethyl-3,3-bis(trimethylsiloxy)tetrasiloxane. 1,2-Benzenedicarboxylic acid Bu 2-ethylhexyl ester is also suggested by database research of the extd. compds. The present study implies that Si is considered to be located in the inner part of the 3-dimensional structure of sporopollenin. .

Excitant activity of methyl derivatives of quinolinic acid on rat cortical neurons

Excitant activity of methyl derivatives of quinolinic acid on rat cortical neurons. Stone, Trevor W. (Med. Sch., St. George's Hosp.Chemicals with cas numbers 85797-13-3 and 89-00-9 also play role., London SW17 0RE, UK). Br. J. Pharmacol., 81(1), 175-81 (English) 1984. CODEN: BJPCBM. ISSN: 0007-1188. DOCUMENT TYPE: Journal CA Section: 1 (Pharmacology) Section cross-reference(s): 2 Various synthetic quinolinic acid analogs were tested for agonist and antagonist properties when applied by microiontophoresis to neurons in the rat cerebral cortex. Quinolinic acid 2-Me ester [24195-07-1] was a weak antagonist of N-methyl-D-aspartate (NMDA) [6384-92-5] and quinolinic acid [89-00-9] but also showed agonist activity, being about 50% as active as quinolinic acid. The excitant effects of the compd. could be antagonized by the NMDA receptor blocker, (±)-2-amino-7-phosphonoheptanoic acid (2APH) [78966-69-5]. N-Methylquinolinic acid 2,3-di-Me ester [73834-99-8] showed very weak agonist and antagonist activity. Homoquinolinic acid [490-75-5] was a potent excitant of cortical neurons, being about 5-times more active than quinolinic acid and approx. equipotent with NMDA. The excitations were blocked by 2APH or its pentanoate analog (±)-2-amino-5-phosphono valeric acid [76326-31-3]. Homoquinolinic acid 2-Me ester [89353-64-0] was also active as an agonist. N-Methyl-DL-glutamic acid [35989-16-3] caused excitation of 5 of the 16 units tested; N-methylglutamate was a weaker agonist than NMDA or homoquinolinate. Phthallic acid [88-99-3], caused excitation of 14 out of 16 units. Thus, the ring nitrogen of quinolinic acid is not essential for excitant activity. Since homoquinolinic acid is a rigid analog of glutamic acid, but causes excitation by acting apparently on the NMDA receptor, the results are consistent with the suggestion that activation of the NMDA receptor may require the carboxyl groups to be held in a relatively extended configuration. .