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1.
Dialkyl β-(2-aroxyethylamino)ethylphosphonates,N-[β-(2-methoxyphenoxy)ethyl]-N′-[β-(diethoxyphosphoryl)ethyl]-α,ω-diaminoalkanes, and diethyl β-(N-arylpiperazino)ethyl-phosphonates were synthesized by the reactions of dialkyl vinylphosphonates with β-aroxyethylamines,N-[β-(2-methoxyphenoxy)ethyl]-α,ω-diaminoalkanes, andN-aryl-piperazines, respectively. The compounds synthesized exhibit hypotensive and α-adrenolytic activities. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 987–991, May 1999.  相似文献   

2.
Ab initio calculations of the molecules of CH3- and CF3-substituted β-propiothiolactones and the productsof their deprotonation were carried out by the restricted Hartree—Fock method with full geometry optimization using the 6–31 G* basis set. Peculiarities of the geometry and electronic structure of the systems in question were established. Only 2-methyl-β-propiothiolactone forms a mesomeric stabilized carbanion in the case of proton abstraction from the α-position of thiolactone cycle. Carbanions of 3-methyl, 2-, and 3-thrifluoromethyl-β-propiothiolactones are stabilized due to the ring opening to form ketene thiolate ions. The CH-acidity of fluorine-containing β-thiolactones is much higher than that of nonfluorinated analogs (the differences in the deprotonation energies are 13.4 to 25.2 kcal mol−1). Deceased. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1719–1725, September, 1998.  相似文献   

3.
Twelve cardiac glycosides and aglycons were isolated from Strophanthus kombe seeds. Of these, eight were identified as cymarin, K-strophanthin-β, K-strophanthoside, periplocymarin, 17α-strophadogenin, erysimin (= helveticoside), erysimoside, and neoglucoerysimoside. Four glycosides, preliminarily designated Sk-x, Sk-y, Sk-z, and Sk-20, were new. Their chemical structures were established as 3β-O-β-D-glucopyranosyl-5β,14β,16β-trihydroxy-19-oxo-17α-card-20(22)enolide (17α-strophadogenin-3-O-β-D-glucoside), 3β-O-β-D-cymaropyranosyl-5β,14β,16β-trihydroxy-19-oxo-17α-card-20(22)enolide (17α-strophadogenin-3-O-β-D-cymaroside), 3β-O-β-D-cymaropyranosyl-4′-O-β-D-glucopyranosyl-6″-O-β-D-glucopyranosyl-5β, 14β,16β-trihydroxy-19-oxo-17α-card-20(22)enolide (17α-strophadogenin-3-O-strophanthotrioside), and 3-O-β-D-digitoxopyranosyl-4′-O-β-D-glucopyranosyl-6″-O-β-D-glucopyranosyl-5β,14β, 19-trihydroxy-card-20(22)enolide (strophanthidol-3-O-gentiobiosyldigitoxoside), respectively. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 156–159, March–April, 2006.  相似文献   

4.
5α-Androstan-3β,17β-diol (3b-adiol), a known inhibitor of prostate cancer cell growth, was synthesized from tigogenin. Its structure was confirmed by NMR and IR spectroscopy and mass spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 81–82, January–February, 2007.  相似文献   

5.
A new type of S-containing terpene lactones was produced by the reactions of limonene-1,2-oxide and β-pinene-α-oxide with mercaptoacetic acid. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 220–223, May–June, 2007.  相似文献   

6.
Levoglucosenone reacts with α-aminoazoles to yield azolo[1,5-a]pyrimidine systems fused with a carbohydrate fragment. The reaction oocurs much more smoothly than in the case of other α,β-unsaturated ketones. The reactions of levoglucosenone with β-dicarbonyl compounds (dimedone, barbituric acid) in the presence of a base results in the pyran ring closure, which has never been observed earlier in reactions of β-dicarbonyl compounds with α,β-unsaturated ketones under the conditions of basic catalysis. The structures of products were established by IR and NMR spectroscopy. For Part 3, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 553–558, March, 1997.  相似文献   

7.
The alkylation of 1,6,8-trihydroxy-3-methylanthraquinone (frangula-emodin) by α-bromoalkylmethylketones was investigated. Hydroxyls in the 1-and 8-positions of the β-derivatives were O-acylated. The compositions and structures of the prepared compounds were confirmed by elemental analysis and UV, IR, PMR, and 13C NMR spectroscopy. __________ Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 324–326, July–August, 2007.  相似文献   

8.
α,α-Dichloro-β-oxoaldehyde diethyl acetals decompose under the action of bases (NaOH, MeONa) with cleavage of the carbon-carbon bond and formation of carboxylic acids or their esters and the dichloroacetaldehyde diethyl acetal carbanion. The latter reactsin situ with benzaldehyde to form stable α-chloro-α,β-epoxyacetal. α-Chloro-α-formyl-γ-butyrolactone diethyl acetal is transformed into α-chloro-α-diethoxymethyl-γ-hydroxybutyric acid under the action of an alkali. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 685–687, April, 1998.  相似文献   

9.
Efficient procedures for the regioselective synthesis of fluoroalkyl-containing threefive-, six-, and seven-membered heterocycles as well as of related fused compounds, namely, α,β-epoxyketones, α,β-aziridinylketones, pyrazoles, pyrazolines, isoxazolines, 1,2-dithiolenes, amino- and mercaptopyrimidines, Δ3,5-2-thioxo-1,3,2-thiazaphosphorines, Δ3,5-2-thioxo-1,3,2-oxazaphosphorines, 2,3-dihydro-1,4-diazepines, azirino[1,2-a]quinoxalines, benzo[b]-and naphtho[2,3-b]-1,4-diazepines, and triazolopyridazines, which have been developed by the authors and coworkers, are summarized. The α- and β-functionalized fluoroalkylcontaining carbonyl compounds (β-diketones, β-ketoesters, their salts, regioisomeric β-aminovinyl ketones, β-aminovinylthiones, β-hydroxyketones, α,β-enones, and their halogen derivatives) were used as synthons in the processes of formation of the above-mentioned heterocycles. Dedicated to the memory of Academician I. Ya. Postovskii on his 100th birthday. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1279–1286, July, 1998.  相似文献   

10.
A new compound of formula C28H48O with mp 179-180°C (aqueous ethanol) that was called eucanbin was isolated pure by column chromatography of the ethanol extract of the aerial part of Eupatorium cannabinum L. The structure 24α-methylcholest-20(21)-en-3β-ol was assigned based on chemical and spectral data. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 318–320, May–June, 2009.  相似文献   

11.
A fraction of sulfated polyhydroxylated steroids from the Far-Eastern starfish Ctenodiscus crispatus was investigated. The main component of this fraction was identified as (22E,24R,25R)-24-methyl-5α -cholest-22-en-3β,5,6β,15α,25,26-hexol 26-O-sulfate. For the compound stereoisomeric with respect to the side chain, the (24R,25S) or (24S,25R) relative configurations were assigned to the C(24) and C(25) chiral centers. The structures of two other compounds isolated from the fraction were identified as (22E, 24ξ)-26,27-bisnor-24-methyl-5α-cholest-22-en-3β,5,6β,15α,25-pentol 25-O-sulfate and (22E, 24ξ,25ξ)-24-methyl-5α-cholest-22-en-3β,5,6β,8,15α,25,26-heptol 26-O-sulfate. Dedicated to Academician N. K. Kochetkov on the occasion of his 90th birthday. __________ Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1229–1234, May, 2005.  相似文献   

12.
New steroid derivatives containing 6-chloropyridine groups characteristic of the alkaloid epibatidine and neonicotinoid insecticides were synthesized by reacting 3β,5α,6β-trihydroxysteroids or 3β,5-dihydroxy-6ketosteroids with 2-chloro-5-chloromethylpyridine. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 180-182, March-April, 2009.  相似文献   

13.
The component composition of essential oils produced by steam distillation from flower heads, leaves, and stems of Salvia anatolica (Lamiaceae), a recently described new species endemic from Turkey, was studied by GC/FID and GC/MS. A total of 127 volatile components representing 96% of the oil was identified in essential oil from flower heads and leaves. It was found that the principal oil components of flower heads and leaves were α-pinene (10.9%), β-pinene (6.7%), α-copaene (6.3%), heptacosane (6.2%), and hexadecanoic acid (5.0%). A total of 109 volatile compounds representing 87.9% of the oil was characterized in essential oil isolated from stems. The principal oil components of stems were identified as hexadecanoic acid (27.2%), tetradecanoic acid (15.2%), dodecanoic acid (5.5%), and α-copaene (5.0%). __________ Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 552–555, November–December, 2007.  相似文献   

14.
α-Halo-β-oxoaldehydes react witho-andm-phenylenediamines to give α-halo-β-oxoenamines. In the case ofo-phenylenediamine, the initially formed monoenamine undergoes concurrent intramolecular cyclization to give benzimidazole and a halocarbonyl compound. α,α-Dihalo-β-oxoaldehydes react witho-andm-phenylenediamines according to the haloformic decomposition scheme involving formylation of amino groups. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 475–477, March, 1998.  相似文献   

15.
In contrast with androsta-1,4-diene-3α/β, 17β-diol, its 3-O-methyl ether is transformed upon C(3)-deprotonation into the corresponding 3-methylene steroid with migration of theO-methyl group on the steroid skeleton (by the scheme of Wittig rearrangement) rather than eliminating the 19-methyl group. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1393–1395, July, 1999.  相似文献   

16.
One new compound 3,7,11,15,19-pentamethyl-9α,10α,11α,17α,18α-pentahydroxy-n-tetracosan-1-oxy-p-hydroxycaffeoate (oryzaterpenyl caffeoate) (1), together with three known fatty acids linoleic acid, stearic acid and myristic acid were isolated and identified from the rice grain of Oryza sativa. The structure of the new compound was elucidated by 1D and 2D NMR spectroscopic techniques (1H-1HCOSY, 1H-13C HETCOR) aided by EI-MS, and IR spectra. __________ Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 535–537, November–December, 2005.  相似文献   

17.
The synthesis of α-amino-β-keto-esters (β-oxo dipeptides) was studied. Corresponding α-amino-β-ketoesters were prepared from BOC-(L)-Valine and BOC-(L)-isoleucine by coupling with (D,L)-threonine hydrochloride and oxidation with Dess-Martin periodinane (DMP) with a total yield of 48% and 38%, respectively. __________ Translated from Chemistry Online, 2007, 70(10): 793–796 [译自: 化学通报]  相似文献   

18.
New esters of 3β,5α,6β-trihydroxysteroids and 3β,5-dihydroxy-6-ketosteroids containing 6-chloropyridine groups characteristic of the alkaloid epibatidine were synthesized by acylation with 6-chloronicotinoylchloride. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 175-179, March-April, 2009.  相似文献   

19.
Methyl trifluoropyruvate reacts with aldehydes in the presence of catalytic amounts of benzoyl peroxide at 130–140°C to give β,β,β-trifluoro-α-(methoxycarbonyl)ethyl carboxylates. UV irradiation makes oligomerization of the initial ketoester predominant. Deceased. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1763–1766, September, 1998.  相似文献   

20.
Asymmetric synthesis of β-N-substituted (S)-α,β-diamino acids was accomplished by Michael addition of amines to the NiII complex of the Schiff base derived from (S)-2-[N-(N′-benzylprolyl)amino]benzophenone (BPB) and dehydroalamine. Diastereoselectivity of the reaction is kinetically and thermodynamically controlled. The chiral auxiliary reagent, BPB, can be recovered and reused. Translated fromIzvestiya Akademii Nauk. Serya Khimicheskaya, No. 3, pp. 504–507, March, 1997.  相似文献   

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