Browsing by Author "CORTES, M"
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- ItemA NOVEL PARTIAL SYNTHESIS OF (-)-WARBURGANAL(1985) RAZMILIC, I; SIERRA, J; LOPEZ, J; CORTES, M
- ItemA NOVEL XANTHONE AS SECONDARY METABOLITE FROM CENTAURIUM-CACHANLAHUEN(1982) VERSLUYS, C; CORTES, M; LOPEZ, JT; SIERRA, JR; RAZMILIC, IFrom the plant C. cachanlahuen, swertiaperenine, swercherine, decusatine, oleanolic acid and the xanthone, 1,8-dihydroxy-2,3,4,6-tetramethoxy-9H-xanthone, were isolated and characterized.
- ItemA SYNTHETIC APPROACH TO RING-B OF FORSKOLIN(MARCEL DEKKER INC, 1993) RAZMILIC, I; LOPEZ, J; CORTES, MA model bicyclic diol (3) incorporating the complete array of oxygenated function of the B ring portion of forskolin (1) has been synthetized using (-)drimenol (2) as starting material.
- ItemACID-CATALYZED REARRANGEMENT OF TREVOAGENIN-A AND TREVOAGENIN-B - THE ACETAL FUNCTION AS ELECTRON-DONOR GROUP IN HETEROLYTIC FRAGMENTATIONS(1983) FRANCISCO, CG; FREIRE, R; HERNANDEZ, R; SALAZAR, JA; SUAREZ, E; CORTES, MThe acid-catalyzed rearrangement of trevoagenins A (1) and B (4) [constituents of Trevoa trinervis] gave 3.beta.-hydroxy-24-oxo-16,17-sec-5.alpha.-dammar-17(20)E-ene-16,30-lactone (5) (40%), its 17(20)Z-ene isomer (7) (13%), and (20R,24R)-3.beta.,25-dihydroxy-15.alpha.,30-cyclo-20,24-epoxy-5.alpha.-dammaran-16-one (9) (2%). Compounds (5) and (7) were produced through a heterolytic fragmentation mechanism. In order to study the scope of this rearrangement the C-20 epimeric hydroxy acetals (24) and (28) were synthesized starting from trevoagenin B and A, respectively. The reaction of the 20S-hydroxy acetal (24) with I led to the Z-olefin (29) while the 20R-hydroxy acetal (28) gave the E-olefin (30). The concerted nature of this heterolytic fragmentation, where acetals or hemiacetals are the electron-donor groups, is supported by the observed stereospecificity of the reaction.
- ItemAN ALTERNATIVE PARTIAL SYNTHESIS OF (-)-POLYGODIAL(1987) RAZMILIC, I; LOPEZ, J; SIERRA, J; CORTES, M
- ItemC-13 NMR-STUDY OF (20,24)-EPOXYDAMMARANE TRITERPENES(1984) FRANCISCO, CG; FREIRE, R; HERNANDEZ, R; SALAZAR, JA; SUAREZ, E; CORTES, M
- ItemCHEMICAL-COMPONENTS OF GUINDILLA SEEDS (VALENZUELIA-TRINERVIS)(1987) SEIGLER, DS; CORTES, M; AGUILERA, JMA cyanolipid has been isolated and characterized from Valenzuelia trinervis (guindilla, Sapindaceae). The seed oil contains primarily oleic (62.3%), gadoleic (12.4%), linoleic (10.1%), and palmitic (9.6%) acids. The leaves of this plant contain approximately 25% saponins of which one predominates. The genin appears to be of triterpenoid origin. The seed meal contains ample lysine, leucine and phenylalanine, but is deficient in methionine. The seed meal is toxic to rats.
- ItemDAMMARANE TRITERPENES OF TREVOA-TRINERVIS - STRUCTURE AND ABSOLUTE STEREOCHEMISTRY OF TREVOAGENIN-A, TREVOAGENIN-B, AND TREVOAGENIN-C(1983) BETANCOR, C; FREIRE, R; HERNANDEZ, R; SUAREZ, E; CORTES, M; PRANGE, T; PASCARD, CTrevoagenins A, B and C, extracted from T. trinervis Miers, were shown by chemical and spectral means to be isomeric dammarane triterpenes possessing the general 3.beta.,25,30-trihydroxy-(20,24)-epoxydammaran-16-one structure with stereoisomeric side-chains of the ocotillol type.
- ItemMICROBIOLOGICAL HYDROXYLATION IN THE DRIMANE SERIES(PERGAMON-ELSEVIER SCIENCE LTD, 1992) ARANDA, G; FACON, I; LALLEMAND, JY; LECLAIRE, M; AZERAD, R; CORTES, M; LOPEZ, J; RAMIREZ, HThe Products of the microbiological hydroxylation of drimenol and related compounds by Mucor plumbeus and Rhizopus arrhizus were investigated. Complementary results (hydroxylation at 3beta- and/or 6alpha-positions) were obtained with both microorganisms.
- ItemNEW APPLICATION OF THE MITSUNOBU REACTION FOR THE PREPARATION OF (DELTA-2) DERIVATIVES IN TERPENIC SERIES(1994) ARANDA, G; LALLEMAND, JY; AZERAD, R; MAURS, M; CORTES, M; RAMIREZ, H; VERNAL, GApplication of the Mitsunobu reaction to various 3 beta-(equatorial)-hydroxy-4,4-dimethyl terpenic compounds provides the 2-ene-derivatives in good yields. A discussion about the mechanisms involved, and full details on the modified experimental protocol are given.
- ItemSYNTHESIS OF (-)-12-NOR-DRIM-9(11)-EN-8-ONE A VERSATILE CHIRAL SYNTHON FOR THE PREPARATION OF NATURAL TERPENOIDS(1989) PENA, W; LOPEZ, JT; CORTES, M
- ItemSYNTHESIS OF (-)-DRIM-7-ENE-9-ALPHA,11,12 TRIOL - THE DIRECT PRECURSOR OF (-)-WARBURGANAL(1982) OYARZUN, ML; CORTES, M; SIERRA, J
- ItemSYNTHESIS OF (-)-ENT-YAHAZUNOL DIMETHYL ETHER(SOCIEDAD CHILENA DE QUIMICA, 1990) CORTES, M; PENA, W; ARMSTRONG, V; LOPEZ, JThe synthesis of (-)-ent-yahazunol dimethyl ether (7) from the unsaturated ketone 2 is described. The present work confirms the proposed absolute configuration of the naturally occuring (-)-yahazunol (1).
- ItemSYNTHESIS OF 1.3 DIOXANES RELATED WITH AMBERGRIS(1984) MATURANA, H; SIERRA, J; LOPEZ, J; CORTES, M
- ItemSYNTHESIS OF AMBRAOXIDE FROM DRIMENOL(1991) MATURANA, H; LOPEZ, J; CORTES, MThe conversion of (-) drimenol (1) into the cyclic ether Ambraoxide (2) is reported.
- ItemSYNTHESIS OF BOTH EPIMERS OF 8-DEMETHYL AMBROX(EDITIONS SCIENTIFIQUES ELSEVIER, 1992) PENA, W; LOPEZ, JT; CORTES, MThe epimers 2 and 3 of the C-8 demethyl analogues of the known ambergris-type odorant Ambrox have been prepared from the chiral enone 4. The latter nor-sesquiterpene is readily available from (-)drimenol via a previously described synthesis.
- ItemSYNTHESIS OF GAMMA-BICYCLOHOMOFARNESAL AND 14,15,16,20-TETRANORLABDAN-8-BETA-13-DIOL(1992) LOPEZ, J; TRESPALACIOS, C; PENA, W; CORTES, MThe preparation of the ambergris odorant, gamma-bicyclohomofarnesal (1) and 14,15,16,20-tetranorlabdan-8-beta-13-diol (4) from chiral enone 5 is described.
- ItemSYNTHESIS OF NATURAL UVIDIN-C(1986) LOPEZ, J; SIERRA, J; CORTES, M