Uncommon Sesquiterpenoids and New Triterpenoids fromJatropha neopauciflora (Euphorbiaceae)

Abstract

Dedicated to Professor Albert Eschenmoser on the occasion of his 80th birthdayEight new terpenoids (1 -8) were isolated from the bark of Jatropha neopauciflora, together with eight known compounds. The new isolates include the sesquiterpenoids (1R,2R)-diacetoxycycloax-4(15)-ene (1) (4), (1R,2R)-dihydroxyisodauc-4-en-14-ol (5) and its acetonide 6 (artifact), as well as the two triterpenoids (3b,16b)-16-hydroxylup-20(29)-en-3-yl (E)-3-(4-hydroxyphenyl)prop-2-enoate (7) and (3b,16b)-16-hydroxyolean-18-en-3-yl (E)-3-(4-hydroxyphenyl)prop-2-enoate (8). The structures of these compounds were established by extensive 1D-and 2D-NMR spectroscopic methods, and their absolute configurations were determined by circular-dichroism (CD) experiments, and by X-ray crystallographic analysis (compound 7; Fig. 3). A plausible biosynthesis of the sesquiterpenoids 1 -5 is proposed (Scheme), starting from (À)-germacrene D as the common biogenetic precursor.

Vasodilator Activity of Compounds Isolated from Plants Used in Mexican Traditional Medicine

“…The purity of the compounds was determined by one dimension or two-dimension thin layer chromatography and in some cases using high performance liquid chromatography. The chemical structure of compounds was determined by 1D or 2D Nuclear Magnetic Resonance techniques as described previously: A. adstringens : 3-α-hydroxymasticadienonic acid ( 1 ) [ 74 ], C. mexicanum : 3α-hydroxytirucalla-7,22 Z -dien-26-oic acid ( 2 ) [ 18 ], C. gracilior : corosolic acid ( 3 ) [ 26 ], C. alamosanus : (3 R ,4 R ,6 S )- p -menth-1-eno-3,6-diol ( 9 ), 5- hydroxy-3,7,4′-trimethoxyflavone ( 17 ), C. glabellus : 6,7-diacetylaustro inulin ( 10 ), and 6- O -acetylaustro inulin ( 11 ) [ 75 ], G. glauca : galphin A ( 4 ), galphin B ( 5 ), galphimidin ( 6 ) [ 24 ], J. neopauciflora : 3β- trans - p -coumaroyl-oxy-16-β-hydroxy-20(29)-lupene ( 7 ), β-sitosteryl β- d -glucopyranoside ( 8 ) [ 19 ], L. tridentata : 3′-demethoxy-6- O -demethyl-isoguaiacin ( 14 ), meso -dihydroguaiaretic acid ( 15 ), 5,4′-dihydroxy-3,7,8-trimethoxyflavone ( 16 ), 5,8,4′-trihydroxy-3,7-dimethoxyflavone ( 18 ) [ 25 ], P. adnata : perezone ( 12 ), and pipitzol ( 13 ) [ 76 ], and T. graveolens : pinostrobin ( 19 ) [ 28 ].…”

“…Gray ( pipitzáhuac ), and Teloxys graveolens ( epazote de zorrillo ). These plants are widely used in Mexican traditional medicine to treat several illnesses, such as gastric ulcers, stomach ache, gastroenteritis, diarrhea, dysentery, sores and infections of the oral cavity, skin ulcers [ 17 , 18 , 19 , 20 , 21 ], renal disorders and kidney stones ( Larrea tridentata ) [ 17 ], cough, asthma, tachycardia and to improve coronary blood flow ( Crataegus gracilior ) [ 20 , 22 ], and cancer ( Croton alamosanus ) [ 23 ].…”

“…The compounds evaluated were previously purified by our research group and our collaborators [ 18 , 19 , 24 , 25 , 26 ] and include: (a) triterpenes: 3-α-hydroxymasticadienonic acid ( 1 ), 3α-hydroxytirucalla-7,22 Z -dien-26-oic acid ( 2 ), corosolic acid ( 3 ), galphin A ( 4 ), galphin B ( 5 ), galphimidin ( 6 ), and 3β- trans - p -coumaroyl-oxy-16-β-hydroxy-20(29)-lupene ( 7 ); (b) sterols: β-sitosteryl β- d -glucopyranoside ( 8 ); (c) diterpenes: (3 R ,4 R ,6 S )- p -menth-1-eno-3,6-diol ( 9 ), 6,7-diacetylaustro inulin ( 10 ), and 6- O -acetylaustro inulin ( 11 ); (d) sesquiterpenes: perezone ( 12 ), and pipitzol ( 13 ); (e) lignans: 3′-demethoxy-6- O -demethyl-isoguaiacin ( 14 ) and meso -dihydroguaiaretic acid ( 15 ); and (f) flavonoids: 5,4′-dihydroxy-3,7,8-trimethoxyflavone ( 16 ), 5-hydroxy-3,7,4′-trimethoxyflavone ( 17 ), 5,8,4′-trihydroxy-3,7-dimethoxyflavone ( 18 ), and pinostrobin ( 19 ) ( Figure 1 ). Although it has been previously demonstrated that some of these compounds possess biological activities, such as antibacterial and antifungal [ 21 , 25 , 27 ], antiprotozoal [ 18 , 24 , 28 , 29 ], anti-inflammatory [ 30 ], anti-diabetic [ 31 , 32 ], and anticancer [ 23 ], at present, there are no studies aimed at assessing their vasodilatory activity.…”

New terpenoids from the roots of Jatropha curcas

“…The 1 H, 13 C NMR, and DEPT (Distortionless enhancement by polarization transfer) data of 1 (Table 1) showed the presence of three methyls (two geminal methyls), three methylenes (one olefinic), seven methines (two oxygenated), and two quaternary carbons (one olefinic). The above-mentioned data, together with the evidence of four degrees of unsaturation suggested that 1 was quite similar to (1R,2R)-dihydroxycycloax-4(15)-ene [14].…”

Sesquiterpene Lactones, Acyl Phenyl Propanoids and Other Constituents from Schkuhria pinnata var. wislizeni. Antioxidant Evaluation

“…As part of our investigations aimed at the characterization of biologically active compounds from the Mexican flora [17], we have undertaken the chemical study of Schkuhria pinnata var wislizeni, a bush distributed in South western and South central United States, Northern and Central Mexico and Mesoamerica [18]. According the botanical reclassification for Schkuhria, S. virgata, S. anthemoidea and other species and their varieties have been recognized as a single species and renamed as S. pinnata var.…”