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1.
Conclusions Simple routes for the synthesis of (2RS, 8R)-(–)-2-propionoxy-8-methyldecane (I) the pheromone of the leaf beetleDiabrotica virgifera virgifera — from chiral monofunctional synthons, obtained from the available (S)-(+)-3,7-dimethyl-1,6-octadiene, were developed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2080–2083, September, 1987.It corresponds to Communication 4 in the series Terpenes in Organic Synthesis. For the preceding Communication, cf. [1].  相似文献   

2.
Summary By separating the total alkaloids ofV.erecta according to their basicities in an APS, in addition to bases known previously we have isolated ervincidine, apovincamine, (+)-quebrachamine, dl-eburnamine, (–)-1,2-dehydroaspidospermidine, and kopsanone. This is the first time that these alkaloids have been obtained from this plant. Thin-layer chromatography showed the presence of another 10–12 uncharacterized alkaloids.The region of the passage into the buffer solutions of some alkaloids has also been established.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 713–717, November–December, 1970.  相似文献   

3.
    
Starting from the readily available enantiomerically enriched (S)-(+)-3,7-dimethylocta-1,6-diene (ee 50%), we have synthesized (4R)-4-methylnonan-1-ol — the sex pheromone of the yellow mealworm bettleTenebrio molitor L. A scheme for synthesizing the racemic analogue of the pheromone from 4-methyltetrahydropyran has been developed.Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 711–714, November–December, 1992.  相似文献   

4.
Enantiomerically pure (14R)-14-methylhexadeca-8Z-enal (cis-trogodermal) — the aggregation pheromone of the khapra beetle (Trogoderma) — and its (14S,8Z)-enantiomer has been effected from di-O-benzoyl-D- and -L-arabinals.Institute of Chemistry, Bashkir Branch, Urals Branch, Russian Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 707–712, September–October, 1991.  相似文献   

5.
Glaser  Robert  Adin  Itay  Drouin  Marc  Michel  André 《Structural chemistry》1994,5(3):197-203
The anorexic drug (+)-(2S, 3S, 4S)-phendimetrazine-2R, 3R)-bitartarate crystallized in the orthorhombic space groupP212121 and at 293 Ka=7.7710(4),b=13.1379(7),c=15.9913(9) Å,V=1632.6(2) Å3,Z=4,R(F)=0.062, andR w (F)=0.026. A chair conformation 2,3-trans-1,4-oxazine ring with equatorially oriented 2-phenyl,3-methyl, andN-methyl substituents was found as predicted by an earlier reported solid-state CP-MAS13C-NMR investigation of crystalline (±)-phendimetrazine bitartarate. The O-CH2-CH2-N torsion angle of –58.4(6)° in the solid-state agrees nicely with the 56.0(7)° dihedral angle value estimated by1H NMR spectroscopy for the major (equatorialN-methyl) phendimetrazine mesylate species in CD2Cl2 solution. A common solid-state conformational arrangement was found for (+)-phendimetrazine and a series of six other anorexic drugs structurally analogous to (+)-(2S, 3S)-pseudoephedrine. In this arrangement, NCH(Me)CPh has (S)-configuration, there is a (–)-gaucheMe-CH-C-Ph torsion angle, an antiperiplanarN-CH-C-Ph torsion angle, and the phenyl ring approximately eclipses the C-H bond of the attached carbon (e.g., H-C-Cipso-Cortho ca. 4° for 2,3-transphendimetrazine). Nonbonded interactions involving the 3-methyl and the 2-phenyl groups open up the H-C-Cipso-Cortho angle in a series of solid-state structures containing the epimeric (–)-(2R, 3S)-ephedrine moiety (e.g., ca. 45° for molecular mechanics calculated 2,3-cis-phendimetrazine model).  相似文献   

6.
    
The synthesis has been achieved of optically active (S)-(+)-14-methyloctadec-1-ene — the sex pheromone of the leaf miner peach mothLyonetia clerkella Linne from the readily accessible enantiomerically enriched (ee 50%) (S)-(+)-3,7-dimethyloct-1,6-diene.Institute of Organic Chemistry, Urals Branch, Russian Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 714–717, November–December, 1992.  相似文献   

7.
Conclusions From the racemes ofC. xanthifolia Fresen. have been isolated a sesquiterpene lactone C16H20O4, the structural (+)-isomer of (–)-coronopilin, which has not been studied previously; structure I has been proposed for it.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 5, pp. 375–377, 1969  相似文献   

8.
Sesquiterpene lactones of the guaianolide type — isolipidiol (I) and 8-epideacylcynaropicrin (II) — have been isolated from narrow-leaf hawk's-beard,Crepis tectorum L. On the basis of the results of an x-ray experiment the structure of (1R, 3S, 5R, 6R, 7R, 8R)-3,8-dihydroxy-cis,trans-guaia-4(15),10(14),-11(13)-trien-6,12-olide is proposed for (II).Institute of Organic Synthesis and Coal Chemistry, Kazakh Academy of Sciences, Karaganda. A. N. Nesmeynaov Institute of Organometallic Compounds, Russian Academy of Sciences, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 638–642, September–October, 1991.  相似文献   

9.
Summary Papaver cumrautatum Fisch. et Mey contains papaverine. FromPapaver fugax Poir we isolated armepavine, floripavine, and two new alkaloids, (+)-isoroemerine and fugapavine, which is 5,6-(methylenedioxy)-3-oxoaporphine.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 502–509, March, 1965  相似文献   

10.
More than 20 compounds have been isolated from the bark ofQuercus robur. Monomers: (–)-epicatechin, (–)-epicatechin gallate, (+)-catechin, (+)-catechin gallate, (+)-gallocatechin, (–)-epigallocatechin, and (–)-epigallocatechin gallate; dimeric proanthocyanidins: (+)-catechin-(4-8)-(+)-catechin, 3-O-galloyl-(+)-catechin-(4-8)-3-O-galloyl-(+)-catechin, 3-O-galloyl-(+)-gallocatechin-(4-8)-(+)-gallocatechin, (–)-epicatechin-(4-8)-3-O-galloyl-(–)-epigallocatechin gallate, 3-O-galloyl-(–)-epicatechin-(4-8)-3-O-galloyl-(–)-epigallocatechin, 3-O-galloyl-(–)-epigallocatechin-(4-8)-(+)-catechin; and oligomeric proanthocyanidins: D14-D19.Materials presented at the IInd International Symposium on the Chemistry of Natural Compounds (SCNC, Eskiehir, Turkey, October, 22–24, 1996).Institute of the Chemistry of Plant Substances, Academy of Sciences of the Republic of Uzbekistan, Tashkent, fax (3712) 40 64 75. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 819–833, November–December, 1997.  相似文献   

11.
    
The isomerization of 5-vinyl-2-norbornene (1) has been studied in the presence of Co (R1-COCHCOR2)x–Et6–yAl2Cly (x=2, 3; y=2–4) catalytic systems. Co(acac)2–AlEt3 and Co(acac)3–AlEt3 systems isomerize1 to 5-ethylidene-2-norbornene (2), whereas the Co(PhCOCHCOPh)2–AlEt3 system selectively forms 3-vinylnortricyclene (3).2 is always accompanied by formation of ethylidene norbornane (4). A possible mechanism for formation of products is proposed.  相似文献   

12.
    
Schemes are proposed for the synthesis of (±)-3-methylheneicosan-2-one and (±)-2-acetoxy-3,7-dimethylpentadecane — racemic analogues of the sex pheromones of the common cockroach (Blatella germanica) and of plane sawflies of the generaDiprion andNeodiprion, respectively, using the reductive -vinylation of -olefins.Institute of Chemistry of the Bashkir Scientific Center, Urals Division of the Russian Academy of Sciences, Ufa. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 567–571, September–October, 1992.  相似文献   

13.
Conclusions (R)-(–)-10-Methyldodecyl acetate, a biospecific minor component of the sex pheromone of the small tea tortrix moth, has been synthesized from the readily accessible compounds (S)-(+)-3,7-dimethylocta-1,6-diene and acrolein.For previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 690–693, March, 1988.  相似文献   

14.
The synthesis of 2′,3′-di-(4-tolylthio)uridine (5) and {1-β-(=D)-[2,3-di-(4-tolylthio)xylofuranosyl]}uracil (7) from (1-β-(=D)-lyxofuranosyl)uracil (3) and uridine, respectively, is described.  相似文献   

15.
A preparative method has been proposed for the synthesis of bicyclic quaternary ammonium salts via sequential treatment of (–)-(1R,2R)- and (+)-(1S,2S)-1-(4-nitrophenyl)-2-amino-1,3-propanediol with paraform followed by an alkyl halide.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1394–1395, October, 1990.  相似文献   

16.
Breast cancer cell proliferation and migration are inhibited by naturally extracted trans-(−)-kusunokinin. However, three additional enantiomers of kusunokinin have yet to be investigated: trans-(+)-kusunokinin, cis-(−)-isomer and cis-(+)-isomer. According to the results of molecular docking studies of kusunokinin isomers on 60 breast cancer-related proteins, trans-(−)-kusunokinin was the most preferable and active component of the trans-racemic mixture. Trans-(−)-kusunokinin targeted proteins involved in cell growth and proliferation, whereas the cis-(+)-isomer targeted proteins involved in metastasis. Trans-(−)-kusunokinin targeted CSF1R specifically, whereas trans-(+)-kusunokinin and both cis-isomers may have bound AKR1B1. Interestingly, the compound’s stereoisomeric effect may influence protein selectivity. CSF1R preferred trans-(−)-kusunokinin over trans-(+)-kusunokinin because the binding pocket required a ligand planar arrangement to form a π-π interaction with a selective Trp550. Because of its large binding pocket, EGFR exhibited no stereoselectivity. MD simulation revealed that trans-(−)-kusunokinin, trans-(+)-kusunokinin and pexidartinib bound CSF1R differently. Pexidartinib had the highest binding affinity, followed by trans-(−)-kusunokinin and trans-(+)-kusunokinin, respectively. The trans-(−)-kusunokinin-CSF1R complex was found to be stable, whereas trans-(+)-kusunokinin was not. Trans-(±)-kusunokinin, a potential racemic compound, could be developed as a selective CSF1R inhibitor when combined.  相似文献   

17.
The catechin and proanthocyanidin compositions of the leaves and bark ofZiziphus jujuba have been studied over the vegetation periods. This has led to the isolation of 16 compounds, including 8 monomeric catechins — (–)-epiafzelechin, (–)-epicatechin, (–)-epigallocatechin, (–)-epicatechin gallate, (–)-epigal-locatechin gallate, (+)-catechin, (+)-catechin gallate, and (+)-gallocatechin; 4 dimeric proanthocyanidins — (–)-epiafzelechin-(4-8)-(–)-epicatechin, proanthocyanidin B-2, (–)-epicatechin-(4-8)-(–)-epigallocatechin, and (–)-epiafzelechin-(4-8)-(–)-epigallocatechin; and 4 oligomeric proanthocyanidins consisting of epiafzelechin, epigallocatechin, catechin, and epicatechin with different degrees of polymerization. Their structures have been established by a study of PMR and13C NMR spectra and the products of chemical transformation.The materials of this paper were presented at the Second International Symposium on the Chemistry of Natural Compounds (SCNC, Eskiehir, Turkey, October 22–24, 1996).Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 221–231, March–April, 1997.  相似文献   

18.
29Si NMR peaks due to species with the double four-membered ring siloxane backbone composed of both Si(O)4/2 and CH3Si(O)3/2 units, (CH3) n Si8O 20 – n /(8 – n) – (n=1–3), formed by co-hydrolysis of tetraethoxysilane and methyltriethoxysilane in the presence of tetramethylammonium ions in methanol have been assigned. It has been found that 29Si NMR peaks due to Si(OSi)3(O) units shift to lower frequencies by replacement of the adjacent Si(O)4/2 units by CH3Si(O)3/2 units, in other words, with increasing m value in Si[OSi(O)3]3 – m [OSi(CH3) (O)2] m (O) (m=0–2). Peaks from CH3 Si(OSi)3 units in the species have also appeared as separated due to the kind of neighbor structural units. On the basis of the assignments, positions of CH3Si(O)3/2 units in the cubic octameric siloxane framework of (CH3) n Si8O 20 – n /(8 – n) – (n=2, 3), for both of which three isomers are present, have been estimated.  相似文献   

19.
The collective fruit of the cocultivatedAllium suvorovii Rgl. andA. stipitatum Rgl. (familyLiliaceae) has yielded a new genin of the spirostan series — anzurogenin A, which is 2,3,5-trihydroxy-(25R)-spirostan-6-one.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 68–73, January–February, 1988.  相似文献   

20.
Reserpine, ajmaline, serpentine, ajmalicine, isoreserpiline, and other alkaloids have been isolated from the roots ofRauwolfia cambodiana Pierre ex Pitard,R. verticillata Baill. andR. serpentina Benth.R. vomitoria Afz. was the richest in alkaloids.Leningrad Institute of Pharmaceutical Chemistry. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 813–816, November–December, 1991.  相似文献   

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