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1.
Reinvestigation of the aerial parts of Matricaria aurea led to the isolation of three new bisabolenes and a new acetylene. The structures of the four compounds, namely (1R*,2R*,3R*,6R*,7R*)1,2,3,6,7- pentahydroxy-bisabol-10(11)-ene, (1R*,2R*,3R*,6R*,7R*)1,2,3,6,7-pentahydroxy-1-acetoxy-bisabol-10(1 1)-ene, (1R*,2R*,3R*,6R*,7R*)1,2,3,6,7-pentahydroxy-2-acetoxy-bisabol-10(1 1)-ene and (3S*,4S*,5R*)-(E)-3,4-dihydroxy-2-(hexa-2,4-diynyliden)-1,6- dioxaspiro-(4,5)decane, were deduced from the high field NMR studies.  相似文献   

2.
Cool LG 《Phytochemistry》2005,66(2):249-260
Ten sesquiterpenes, many with unusual carbon skeletons, were identified in foliage of Cupressus macrocarpa. These are (-)-10-epi-beta-acoradiene; ent-widdra-2,4(14)-diene; (E)-iso-gamma-bisabolene, i.e., (4E)-4-(1,5-dimethylhex-5-enylidene)-1-methylcyclohexene; (-)-cumacrene, i.e., (4S)-4-[(1R,2S)-2-isopropenyl-1-methylcyclobutyl]-1-methylcyclohexene; (-)-alpha-chamipinene, i.e., (1S,6S,7S)-2,2,6,8-tetramethyltricyclo[5.3.1.01,6]undec-8-ene; and five sesquiterpenes with a 3,3,4'-trimethyl-1,1'-bi(cyclohexyl) skeleton for which the trivial name macrocarpane is proposed. The possible single-enzyme biogenesis of these sesquiterpenes is discussed.  相似文献   

3.
Stereoisomers of the tetrahydro-beta-carboline derivative, 1-(2-pyrrolidinethione)-3-yl)-1,2,3,4-tetrahydro-beta-carboline- 3-carboxylic acid (PTCC), were formed from L-tryptophan with 4-methylthio-3-butenyl isothiocyanate, and their mutagenic properties and contents in different types of the radish products were studied. The isomers were identified as (1S*, 3S*, 3R*)- and (1R*, 3S*, 3R*)-PTCCs; the former was found as the major compound but had no mutagenic activity, while the latter was mutagenic toward Salmonella typhimurium TA 98 in the presence of a rat microsomal fraction. Both (1S*, 3S*, 3R*)- and (1R*, 3S*, 3R*)-PTCC were detected in a ratio of about 4:1 in a product fermented for 8 months, but only a trace was apparent in products manufactured within a few weeks.  相似文献   

4.
The known complex trans-RuCl2(NBD)Py2 (1, NBD is norbornadiene, Py is pyridine) reacts with either (R)-BINAP ((R)-2, 2'-bis(diphenylphosphino)-1,1'-binaphthyl), (S;S)-Chiraphos ((2S;3S-(-)-2,3-bis(diphenylphosphino)butane), (S;S)-Skewphos ((2S;4S)-(-)-2,4-bis(diphenylphosphino)pentane), (R)-(S)-Josiphos ((R)-(-)-1-[(S)-2-(diphenylphosphino)ferrocenyl]ethyl-dicyclohexylpho sphine), (R;R)-Norphos ((2R;3R)-(-)-2, 3-bis(diphenylphosphino)bicyclo[2.2.1]hept-5-ene), or (R;R)-Me-DUPHOS ((-)-1,2-bis((2R;5R)-2, 5-dimethylphospholano)benzene) to generate in high yields the crystalline complexes trans-RuCl2(P-P*)Py2 (P-P* is the corresponding chiral bis(phosphine)). The complexes trans-RuCl2(P-P*)Py2 are active enantioselective hydrogenation catalysts for ketoesters and noncarboxylic olefins in the presence of small amounts of HBF4 (aq.). They are active for hydrogenation of carboxylic substrates in the presence of Et3N. Reaction of trans-RuCl2(P-P*)Py2 with (rac)-1,2-diphenylethylene-diamine (N-N*, either enantiomer) forms in good yields the corresponding compounds trans-RuCl2(P-P*)(N-N*). Representative hydrogenations with these catalysts are presented.  相似文献   

5.
Two new jatropham derivatives and three new steroidal saponins were isolated from the fresh bulbs of Lilium hansonii, along with previously known compounds. The structures of the new compounds were elucidated, on the basis of spectroscopic data and chemical evidence, and by comparing them with those of known compounds, as (-)-5-hydroxy-3-methyl-3-pyrrolin-2-one (jatropham) 5-O-beta-D-glucopyranosyl-(1----3)-beta-D-glucopyranoside, (2S*,4R*)-1-(3-methyl-2-oxo-3-pyrrolinyl)-4-methyl-5-oxo-2-pyrr olidinecarboxyli c acid, 26-O-beta-D-glucopyranosyl-(25R)-5 alpha-furostan-3 beta,22 zeta-diol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside, (25R)-5 alpha-spirostan-3 beta,12 alpha-diol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside and (25R)-spirost-5-en-3 beta,12 alpha-diol 3-O-alpha-L-rhamnopyranosyl-(1----2)-O-[beta-D-glucopyranosyl-(1----4)]- beta-D-glucopyranoside, respectively. The stereostructure of jatropham dimer, the plain structure of which was presented previously, was confirmed by X-ray crystallographic analysis. The inhibitory activity on cyclic AMP phosphodiesterase of the steroidal saponins was evaluated.  相似文献   

6.
Three known and two new diterpenes were isolated from the ethyl acetate extract of Hymenaea courbaril var. stilbocarpa seed pods. One of the compounds was elucidated as (5R*,8S*,9S*,10R*)-cleroda-3,13E-dien-15-oic acid and the other was elucidated, after treatment with diazomethane, as methyl (5S*,8S*,9S*,10R*)-cleroda-3,13E-dien-15-oate. The known diterpenes were identified as (-)-ozic acid, (-)-isoozic acid and (-)-kovalenic acid which were characterized as their methyl ester derivatives.  相似文献   

7.
Oxygenated lycopenes, (2S*,5S*,6R*)-2,6-cyclolycopene-1-methoxy-5-ol, (2S*,5S*,6R*)-1,16-didehydro-2,6-cyclolycopene-5-ol and (3R,6'R)-3-hydroxy-3',4'-didehydro-beta,gamma-carotene (anhydrolutein I) were isolated from tomato puree. The structures of these compounds were elucidated on the basis of spectroscopic evidence.  相似文献   

8.
The synthesis of methyl (-)-shikimate [(-)-2] was achieved via lipase-catalyzed optical resolution of (1S*, 4R*, 5R*)-4-hydroxy-6-oxabicyclo[3.2.1]oct-2-en-7-one (3). Transesterification of (+/-)-3 and vinyl acetate with lipase MY and subsequent hydrolysis gave optically pure (-)-3. This compound was converted to (-)-2 in two steps.  相似文献   

9.
The sesquiterpenoid ketone, 1,4,4-trimethyltricyclo[5.4.0.0(3.5)]undec-7-en-9-one (1), was subjected to microbial transformation by six fungal strains: Aspergillus niger ATCC 9142, Aspergillus ochraceus DSM 824, Beauveria bassiana ATCC 7159, Cunninghamella echinulata ATCC 9244, Rhizopus arrhizus ATCC 11.145, and Absidia blakesleeana ATCC 10.148. Four main metabolites were formed from 1: 10(R)- and 10(S)-hydroxy-1,4,4-trimethyltricyclo-[5.4.0.0(3.5)]undec-7- en- 9-one (2 and 3, respectively), besides 4(R)- and 4(S)-(hydroxymethyl)-1,4-dimethyltricyclo[5.4.0.0(3.5)]undec -7-en-9-one (4 and 5, respectively). Compounds 2-5 were isolated with varying percentages from the respective transformations, and their structures established unequivocally by a combination of spectroscopic methods. Metabolites 2 and 3 are products of hydroxylation at C-10, in either R- or S-position; in 4 and 5, one geminal CH3 group each on the cyclopropane ring has been transformed into a CH2OH function.  相似文献   

10.
Two compounds identified as 7,7-dimethyl-2-methylenebicyclo[3.1.1]heptan-6-ol acetate and 6,6,8,9-tetramethyltricyclo[3.3.3.0]undec-7-en-2-ol were isolated from the essential oil of the fresh leaves of Psiadia anchusifolia. Their structures were determined by extensive NMR studies (1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC) as well as by X-ray crystallographic analysis.  相似文献   

11.
From the bark of Tapiria obtusa, six alkyl phenol derivatives were isolated: 1-hydroxy-3-[(Z)-7'-nonadecenyl]-benzene, 1-hydroxy-3-[(Z)-7'-heptadecenyl]-benzene, 1-hydroxy-3-[14'-phenyltetradecyl]-benzene, and 1-hydroxy-3-[16'-phenyltetradecyl]-benzene, and their possible biogenetic precursors, 1-(16'-phenyl-12'Z-hexadecenyl)-4-Z-cyclohexene-(1S*,3S*)-diol and (4S*,6S*)-dihydroxy-6-(14'Z-nonadecenyl)-2-cyclohexenone. The structures of these compounds were elucidated by chemical and spectroscopic analysis, (4S*,6S*)-Dihydroxy-6-(14'Z-nonadecenyl)-2-cyclohexenone showed cytotoxic activity.  相似文献   

12.
Arai MA  Kuraishi M  Arai T  Sasai H 《Chirality》2003,15(1):101-104
New chiral bis(isoxazoline) ligands bearing a spiro[5.5]undecane skeleton were designed and synthesized in five steps from diethyl malonate (3). These ligands showed a coordinating ability to Cu(II) as chiral ligands. A complex of (+)-(M*,S*,R*)-[5.5]-SPRIX 2b and Cu(OTf)(2) catalyzed the conjugate addition of diethyl-zinc to 2-cyclohexenone (8) to give (S)-3-ethyl-cyclohexanone (9) in 93% yield with 54% ee.  相似文献   

13.
This report is devoted to study of the hydrocarbon composition of the extract of buds of birch (family Betulaceae). We identified 3,5-dihydroxy-7,4??-dimethoxyflavone, 5,7-dihydroxy-3,4??-dimethoxyflavone, 7-methoxy-4??,5-dihydroxyflavanone, 4??-methoxy-5,7-hydroxyflavanone, 5??,6??-dihydroxycaryophyllen-4(14),8(15)-diene ((1R,5R,6R,9S)-5,6-dihydroxy-11,11-dimethyl-4,8-methylenebicyclo[7.2.0]-undecane), 5??,6??-dihydroxycaryophyllen-3,8(15)-diene ((1R,5R,6R,9S)-5,6-dihydroxy-11,11-dimethyl-8-methylenebicyclo[7.2.0]undec-3-ene), 6??,9??-dihydroxy-??-humulene((1E,4E,6R,9S)-6,9-dihydroxy-4,11,11-trimethyl-8-methylene-1,4-cycloundecanediene), 5??,6??,8??-trihydroxycariolan, and (1R,5R,6R,8R,9S)-trihydroxycariolan. The gas chromatographic retention indices of all identified compounds were determined.  相似文献   

14.
From solid cultures of the biologically important endophyte Streptomyces species LR4612, cultivated on Maytenus hookeri, four new and two known compounds were isolated. The new compounds were identified as (2S*,3S*)-5-amino-3-hydroxy-5-oxopentan-2-yl 3-(formylamino)-2-hydroxybenzoate (1), N-[(3R*,4R*)-3-amino-3,4-dihydro-4-methyl-2,6-dioxo-2H,6H-1,5-benzodioxocin-10-yl]formamide (2), (5beta,6alpha)-6,11-dihydroxyeudesmane (3), and 5-(6,7-dihydroxy-6-methyloctyl)furan-2(5H)-one (4); the known compounds were elucidated as sorbicillin (5) and N-acetyltyramine (6). The structures were established by HR-ESI-MS and in-depth NMR analyses.  相似文献   

15.
The influence on the insecticidal activity of haedoxan A of its 3-(3,4-methylenedioxyphenyl) group in the 1,4-benzodioxanyl moiety was examined with two (±)-(1S*,2R*,5R*,6S*)-6-[(2R*,3R*)-3-alkyl-6- methoxy-2-methoxymethyl-1,4-benzodioxan-7-yl]-2-(2,6-dimethoxyphenoxy)-1-hydroxy-3,7-dioxabicyclo-[3.3.0]octanes. Replacement of the methylenedioxyphenyl group of haedoxan by methyl and n-butyl group resulted in a large decrease in the activity, indicating the importance of the 3-aryl group for the potent insecticidal activity of haedoxan.  相似文献   

16.
Dai JQ  Liu ZL  Yang L 《Phytochemistry》2002,59(5):537-542
Six non-glycosidic iridoids, i.e. (1R,4S,4aS,7S,7aS)-7-hydroxyl-4-hydroxy- methyl-7-methyl-1-methoxyl-1,4,4a,7a-tetrahydrocyclopenta[e]pyran-3-one (1), (1S,4R,4aS,7S,7aS)-7-hydroxyl-4-hydroxymethyl-7-methyl-1-methoxyl-1,4,4a,7a-tetrahydrocyclopenta[e]pyran-3-one (2), (1R,4R,4aS,7S,7aS)-7-hydroxyl-4-hydroxy-methyl-7-methyl-1-methoxyl-1,4,4a,7a-tetrahydrocyclopenta[e]pyran-3-one (3), (1R, 4R, 4aS, 7aS)-4,7-dihydroxymethyl-1-methoxyl-1,4,4a,7a-tetrahydrocyclopenta-6-ene[e]pyran-3-one (4), (1R, 4R, 4aS, 7aS)-4,7-dihydroxymethyl-1-hydroxyl-1,4,4a, 7a-tetrahydrocyclopenta-6-ene[e]pyran-3-one (5), (1R, 4S, 4aS, 7aS)-4,7-dihydroxy-methyl-1-methoxyl-1,4,4a,7a-tetrahydrocyclopenta-6-ene[e]pyran-3-one (6), as well as five known non-glycosidic iridoids mussaenin A (7), gardendiol (8), isoboonein (9), 4-epi-alyxialactone (10) and rehmaglutin D (11) have been isolated from the Chinese medicinal plant Cymbaria mongolica. Their structures were elucidated by spectroscopic methods. These compounds exhibit significant antitumor and antibacterial activity.  相似文献   

17.
An asymmetric transformation of racemic t-butyl 2-(3,4-O-carbonyldioxy-phenyl)-2-(phthalimidooxy)acetate [(RS)- 2b ] into one of its optically active forms was carried out by a combination of preferential crystallization of a desired enantiomer and the simultaneous racemization of the antipode. (R)- 2b was easily racemized in diethylketone in the presence of a small amount of 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU). Under the conditions for racemization, the asymmetric transformation was achieved successfully to give (S)- 2b with 84% optical purity in 80% yield. A potent antipseudomonal cephalosporin M-14659 ( 1 ) was prepared from the pure (S)- 2b which was obtained by the recrystallization of the crude (S)- 2b . © 1993 Wiley-Liss, Inc.  相似文献   

18.
Two groups of sphingolipids 1 and 2 were isolated from the aerial parts of Euphorbia sororia. On the basis of spectroscopic data, chemical methods and GC-MS analysis, the structures of 1 and 2 were characterized as 1-O-beta-D-glucopyranosyl-(2S,3S,4R,8Z)-2-[(2'R)-2'-hydroxydocosanoyl approximately hexacosanoyl, octacosanoyl amino]-1,3,4-octadecanetriol-8-ene and (2S,3S,4R,8E)-2-[(2'R)-2'-hydroxyeicosanoyl approximately hexacosanoyl amino]-1,3,4-octadecanetriol-8-ene, respectively. Both of them exhibited marked neuritogenic activity on the rat pheochromocytoma PC12 cell line.  相似文献   

19.
2-Methyl-3-phenylcyclopropylmethyl 3-phenoxybenzyl ether 2 and cyanohydrin ester 3, a couple of pyrethroids with three asymmetric centers, were synthesized. Of each of the four diastereomers of 2 and 3, only the (1R*,2R*,3R*)-2a and 3a showed significant insecticidal activities. Dual sets of enantiomers [(1R,2R,3R)-(-)-2a and (1S,2S,3S)-(+)-2a] and [(1R,2R,3R)-(-)-3a and (1S,2S,3S)-(+)-3a] were synthesized through the asymmetric cyclopropanation using the Aratani catalyst. Significant separations of insecticidal activities were observed between both the enantiomers against the tobacco cutworm (Spodoptera litura) and the common mosquito (Culex pipiens pallens); (1S,2S,3S)-(+)-2a and (+)-3a showed higher activities than their antipodes (1R,2R,3R)(-)-2a and (-)-3a. This result is the second example of such synthetic pyrethroids with three asymmetric centers.  相似文献   

20.
A series of phosphonate analogues of the antiviral cyclopropane nucleoside A-5021 were synthesized from (1S*, 7R*)-3,5-dioxa-4,4-diphenylbicyclo[5. 1.0]octane-l-methanol by a 10-step process. In contrast to the potent antiherpetic activity of A-5021, they were all devoid of antiviral activity.  相似文献   

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