Journal of Natural Products
3 34
mol. 50, No. 2
COUMARINS FROM PEREZIA CARTHAMOIDES
EDUARW GUERREIRO Departamento de Quimica Orginica, Facultad de Quimira, Bioquimira y Farmaria, UniversidzdNacional de San L i s , Charabucoy Pedmrca, 5700 San Lwic, Argentina and PEDROJOSEPH-NATHAN
Departamento de Quimica, Cmtro dc Ivertigacih y de EstrUiios Avanzados, lnstituto PolitCnico NasionaI, P . O . Box 14-740, Mkxico, D.F., 07000 Mixico As part of a general phytochemical investigationof the Argentinan region of Cuyo, we studied P m i a rarthamoider (D. Don) Hook. et Am. (Compositae), this being the third species ofthe South American section P m i a (1) of the genus P m i a that has been investigated. Chromatographicseparation of the partitioned methanolic extracts of the dried roots yielded 3,4,8trimethoxy-5-methylcoumarinand 8-hydroxy-4-methoxy-5-methylcoumarin. Both compounds were identified by ir, ‘H nmr, I3C nmr, ms, and direct comparison. The trimethoxymethylcoumarinwas previously isolated from P m i a multifia (2,3) collected in Ecuador, while the other was isolated from P m i a cocnrle~cens(4) collected in P e d Highly oxidized coumarins may be chemotaxonomically significant metabolites of South-American P m k .
EXPERIMENTAL
PLANT x s m ~ . - T h e plant was collected in the vicinity of the Laguna Horcones, Mendoza, Argentina in March 1986. A voucher specimen (Ambrosetti 1665)is deposited in the Ruiz Leal herbarium (MERL), Mendoza, Argentina. EXTRACTION AND ISOLATION.-The airdried mots (1.2 kg) were ground and extracted at room temperature with MeOH (3 times X 24 h), and the solvent was removed under reduced pressure. The crude extract was partitioned between MeOH-H,O (9: 1) and n-hexane and, after removal of the hexane soluble part, between MeOH-H,O (7:3) and CHCI,. The CHCI, layer was adsorbed on Si gel packed in C6H6and eluted with C6HfltOAc mixtures of increasingpolarity. The early fractions contained 3,4,8-trimethoxy5-methylcoumarin, and the later fractions gave 8-hydroxy-4-methylcoarin. Complete purification of the compounds was achieved by rechromatography followed by crystallization to afford 17 and 22 mg, respectively. ACKNOWJlDGMENTS Weare thankful to Prof. J. KavkaandLic. F.H. Guidugli, LEA(UNSL)formsand toIng. J.A. Ambrosetti, IADIZA (Mendoza) for plant collection and botanical assistance. The work was supported by a grant from CONICET (Argentina).
LITERATURE CITED 1.
2.
3. 4.
B.S. Vuilleumier, “The Systematicsand Evolution o f P m i a SectionPerezia,”The Gray Herbarium of Harvard, Cambridge, 1970. P. Joseph-Nathan, J. Hidalgo, and D. Abramo-Bruno, Phytocbnistry, 17,583 (1978). F. Bohlmann and C. Zdero, Phytochemistry, 16, 239 (1977). L.R. Angela, 0. Look de U., I.C. Salkeld, and P. Joseph-Nathan, Phytochemistry, 23,2094 (1984).
Received 5 August I986
