Piqueria

Studies on Piqueria trinervia. A very interesting study is that of the allelopathic potential of Piqueria trinervia and its piquerols A and B, by Gonzalez de la Parra et al. (14). It was found that this widely distributed weed in the Valley of Mexico has a wide biological activity upon other plants. 

There is still little synthetic work toward the main terpenes of the o-menthane group (see Vol. 4, p. 527). Synthesis of the methyl ether 683 and its isomer 684 from, respectively, 2-methoxy-6-methylbenzoic acid and 3-methoxy-2-methylbenzoic acid showed that e substance isolated by Bohlmann from Piqueria trinervia was 683, and not 684, as he had believed. ... 

Tetramethylcydohexanes.—Aldehydo-esters (169 R = OAc, OH, or H) related to isoferulol have been isolated from Piqueria trinervia " and the structures of the furocoumarin ethers iselin and iliensin (Vol. 7, p. 35) have been revised and shown by synthesis to be derivatives of )3-cyclolavandulol (170).Cocker etal. 

Piqueria trinervia is a perennial herb, which grows in tropical and temperate zones of Mexico, Central America and Haiti. It has been sometime mistakenly cited as Stevia serrata. In Mexico, it is found at an... 

Piqueria trinervia possible herbicidal activity has been thoroughly studied. It was first demonstrated that piquerol A (26a) inhibited the germination and plant growth of several weeds, therefore it was proposed as responsible of P. trinervia allelopathic activity [52]. The mechanism of action of piquerol A was next studied [53]. This compound inhibited ATP synthesis and phosphorylating electron rate in pea chloroplasts. On the... 

Pioneering plants of disturbed habitats often produce active monoterpenes. (+ )-Pulegone (29) was four times, and (-1-)- and ( —)-camphor two times more toxic to seeds and seedlings of Raphanus sativus (Brassicaceae) than HCN (Asplund, 1968). The Mexican plant Piqueria trinervia (As-teraceae) produced monoterpene diols, piquerol A (82) and B (83), that strongly inhibited root and stem growth of competing plants at 50-200 ppm. 

Bohlmann F, Suwita A 1978 New Tferpene derivatives from Piqueria trinervia. Phytochemistry 17 560-561... 

Jimenez, E.M., and M. Gonzalez de la Parra nuevo alcohol diterpenico aislado de Piqueria trinervia Cav. Rev. Latinoamer. Quim. 14, 20 (1983). 

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