Chemistry of furan and thiophene compounds

1-(-Furyl)pentan-1-ol-3-one and 1-(-thienyl)pentan-1-o1-3-one were synthesized by the reaction of furfural and -formylthiophene with methyl ethyl ketone. The products were used to synthesize secondary-tertiary -glycols with -furyl and -thienyl groups attached to the secondary carbinol carbon. It was proved that these -glycols are capable of undergoing hydrolytic cleavage at the C₂–C₃ bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 295–297, March, 1972.     

Triterpene glycosides ofHedera taurica. XI. Structures of taurosides St-G1, St-H1, and St-H2 from the stems of Crimean ivy

The previously known glycosides 3-O--L-arabinopyranosyl-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin and 3-O-[-L-rhamnopyranosyl-(12)-O--L-arabinopyranosyl]-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin and the new triterpene glycoside tauroside St-H₁ — 3-O--D-glucopyransyl-28-O-[-L-rhamnopyranosyl-(14)-O--D-glucopyranosyl-(16)-O--D-glucopyranosyl]hederagenin — have been isolated from the stems ofHedera taurica Carr.M. V. Frunze Simferopol' State University. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 571–579, July–August, 1993.     

Electrochemically induced Favorsky rearrangement: transformations of dialkyl ketones into α,β-unsaturated carboxylic esters

Electrolysis of dialkyl ketones in MeOH in the presence of the NaI—NaOH mediator system placed in an undivided cell involves a process analogous to the Favorsky rearrangement of ,-dihalodialkyl ketones giving rise to methyl esters of ,-unsaturated carboxylic acids in 70—75% substance yields and 60—70% current yields.     

Triterpene glycosides from Pulsatilla chinensis

Four triterpene glycosides were isolated from the roots of Pulsatilla chinensis (Bunge) Regel (Ranunculaceae). Two new glycosides, chinensiosides A (1a) and B (2), were identified as 3-O-[-L-rhamnopyranosyl-(12)--L-arabinopyranosyl]-28-O-[-L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl]-3,23-dihydroxylup-20(29)-en-28-oic acid and 3-O-{-L-rhamnopyranosyl-(12)-[-D-glucopyranosyl-(14)]--L-arabinopyranosyl}-28-O-[-L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranosyl]-3,23-dihydroxylup-20(29)-en-28-oic acid. The other two glycosides were identified as previously known hederasaponin C (3) from Hedera helix and glycoside III (4) from Pulsatilla cernua.     

Complex formation of unsaturated cyclodextrin solutions with various polymers

By using methyl orange as a competitive complexant, it was shown that solutions of poly(ethylene glycol), poly(propylene glycol) and poly(N-vinylpyrrolidone) equivalent to a concentration of 1.67 mM monomer are able to form soluble inclusion complexes with 0.20 mM solutions of -, - and -cyclodextrins. The complex formation is independent of polymer chain length. Poly(ethylene glycol) solutions complexed, on average with 40%, 45% and 75% of -, -, and -cyclodextrin, respectively. A poly(propylene glycol) solution complexed 55% -cyclodextrin, 80% -cyclodextrin and 90% -cyclodextrin. Poly(N-vinylpyrrolidone) solutions complexed on average with 90% of -, -, and -cyclodextrin.     

New cardenolides from the leaves ofGomphocarpus fruticosus

Two new glycosides, gomphotin (1) and gomphotoxin (13), and also the known gomphoside (9) have been isolated from the leaves ofGomophocarpus fruticosus. Compounds (1) and (9) contain a 4,6-dideoxyhexosulose residue as the sugar component, and (13) a 6-deoxyhexosulose, which are attached to glycolic OH groups of the aglycons by 3-O-1,2-O-2 (9, 13) and 3-O-1,4-O-2 (1) acetal-ketal bonds. The structures of the new compounds are represented by the names (3-O-1,4-O-2)-(2,3-dihydroxy-4, 6dideoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (1) and (3-O-1,2-O-2)-(2,3,4-trihydroxy-6-deoxyhexulosido)-14-hydroxy-5-card-20(22)-enolide* (13).State Scientific Center for Drugs of the Ministry of Health and the National Academy of Sciences of the Ukraine, Kharkov, fax 441118. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 824–832, November–December, 1995. Original article submitted May 22, 1995.     

Mass spectrometric study of monoalkyl-substituted thiacyclanes

Monosubstituted - and -alkylthiophans and -, -, and -alkylthiacyclohexanes were subjected to a comparative mass spectrometric study. The stability of the M⁺ ion increases on passing from - to -alkylthiophans and from - to - and -alkylthiacyclohexanes. In the case of -alkylthiophans and - and -alkylthia-cyclohexanes the principal process is associated with ejection of the substituent as a whole, whereas a portion of the alkyl substituent, with retention of one CH₂ group in the composition of the charged fragment, is eliminated from the molecular ions of -alkylthiophans and -alkylthiacyclohexanes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 176–181, February, 1978.     

Transformed steroids. 160. Reaction of 20,20-dimethoxy-16α,17α-epoxypregn-5-ene-3β, 21-diol-20-one with pyridine thiocyanate and carbethoxyhydrazine

Conclusion The reaction of 20,20-dimethoxy-16,17-epoxypregn-5-ene-3,21-diol-20-one with pyridine thiocyanate in the presence of carbethoxyhydrazine proceeds by two competing paths: cisopening of the oxide ring by a -SCN ion at the C¹⁷ atom, and substitution of one of the methoxyl groups by -NCS ion. As a result 2,20-dicarbethoxyhydrazones of pregn-5-ene-3,21-diol-20-one-[17,16-d]-1,3-oxathiolan-2-one and 20-methoxy-16,17-epoxypregn-5-ene-3-ol-[20,21-d]-1,3-oxazolidine-2-thione are formed.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 911–914, April, 1987.     

Mono- and sesquiterpenoids of the oleoresin ofAbies nephrolepis. Crystal structure of (+)-β-cedrol

The composition of the mono- and sesquiterpenoids from the oleoresin of the Khingan fir has been studied. Thirteen monoterpenoids have been identified — bornyl acetate, -terpenyl acetate, geranyl acetate, citronellyl acetate, -fenchyl acetate, linalool, geraniol, terpineol-4, -terpineol, -fenchol, borneol, sabinene hydrate and thymol methyl ether; and 19 sesquiterpenoids — -longipinene, longicyclene, longifolene, -copaene, -ylangene, sibirene, -and -selinenes, - and -cadinenes, -muurolene, caryophyllene, -humulene, - and -bisabolenes, ar-curcumene, nerolidol, bisabolol, and -cedrol. The crystal structure of -cedrol has been investigated by x-ray structural analysis.Novosibirsk Institute of Organic Chemistry, Siberian Branch, Academy of Sciences of the USSR. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 41–45, January–February, 1985.     

The synthesis of vinyl naphthalenes with fluorinated side chains

Summary Methods for the synthesis of -fluoro--vinyl naphthalene and -difluoromethyl--vinylnaphthalene were developed.     

Triterpene glycosides of Pulsatilla dahurica structures of glycosides A,B, C,and D

The isolation of four triterpene glycosides from the roots of the dahurian anemonePulsatilla dahurica (Fisch. ex DC) Spreng, is described together with their identification, on the basis of chemical transformations, spectral characteristics, and literature analogies, as hederagenin 3-O--L-arabinoside, hederagenin 3-O-[O--D-glucopyranosyl-(12)--L-arabinopyranoside], hederagenin 3-O--L-arabinopyranoside 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside], and hederagenin 3-O-[O--D-glucopyranosyl-(14)--L-arabinopyranoside] 28-O-[O--L-rhamnopyranosyl-(14)--D-glucopyranosyl-(16)--D-glucopyranoside].Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, Russian Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, Nos. 3,4, pp. 349–356, May–August, 1992.     

Condensation of formaldehyde with trifluoroethylene

Summary The condensation of trifluoroethylene with paraformaldehyde in the presence of sulfuric and chlorosulfonic acids has been carried out. -Fluorohydracrylic, -fluoro--chloropropionic, and -fluoro--bromopropionic acids have been obtained.     

13C NMR spectra of acetylated methyl glycosides of monosaccharides

Summary A comparative discussion of the signals in the¹³C NMR spectra of acetylated methyl - and -D-xylopyranosides, - and -D-glucopyranosides, - and -D-galactopyranosides, - and -L-arabinopyranosides, - and -L-fucopyranosides, and - and -L-rhamnopyranosides and of the corresponding free glycosides has shown a similarity of the effects of substitution at C₅ with a longer-range nature of these effects in the case of the acetylated glycosides.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center of the Academy of Sciences of the USSR, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 6–8, January–February, 1979.     

Minor polyhydroxysteroids from the starfish Crossaster papposus

Minor polyhydroxysteroids from the starfishCrossaster papposus have been isolated and characterized: 5-cholestane-3,6,8,15,16,26-hexanol and 24-methyl-5-cholesta-14,22E-diene-3,6,8,26-tetraol 26-O-(3-O-methyl--D-glucopyranoside) (crossasteroside P₃). The structures of the compounds were established on the basis of spectral methods.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Branch, USSR Academy of Sciences, Vladivostok. Translated from Khimiya Prirodnykh Soedinenii, No. 2, p. 218–221, March–April, 1990.     

Synthesis of 2,3-dioxo-2,3-dihydro-4-methyl-6-chloro-1H-pyrrolo[2,3-b]pyridine and its 1-α-L-arabinopyranoside

A new type of isatin analog-2,3-dioxo-2,3-dihydro-4-methyl-6-chloro-1H-pyrrolo[2,3-b]pyridine — was obtained by oxidation of 4-methyl-6-chloro-1H-pyrrolo(2,3-b]pyridine. Condensation of L-arabinose with 4-methyl-6-chloro-2,3-dihydropyrrolo[2,3-b]pyridine and subsequent acetylation and dehydrogenation gave 1-(2,3,4-tri-O-acetyl--L-arabinopyranosyl)-4-methyl-6-chloropyrrolo[2,3-b]pyridine, which served as the starting compound for the synthesis of 1--L-arabinopyranosyl-4-methyl-6-chloropyrrolo[2,3-b]pyridine. Oxidation of 1-(2,3,4-tri-O-acetyl-L-arabinopyranosyl)-4-methyl-6-chloropyrrolo[2,3-b]pyridine gave 1-(2,3.4-tri-O-acetyl--L-arabinopyranosyl)-2,3-dioxo-2,3-dihydro-4-methyl-6-chloropyrrolo [2,3-b]pyridine.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1083–1086, August, 1977.     

β-(4-Nitrophenyl)-α,α′-dichlor-hydracrylsäure

Zusammenfassung Basenkatalysierte Kondensation von 4-Nitrobenzaldehyd mit Dichloracetonitril in Methanol lieferte ein als Methyliminoäther aufgefaßtes Kondensationsprodukt, dessen salzsaure Hydrolyse die im Titel genannte Säure ergab. Sie erwies sich als völlig ident mit einem Präparat, das in einer vorigen Arbeit durch Hydrolyse des 2-[-(4-Nitrophenyl)--oxy-,-dichlormethyl]-oxazolin erhalten wurde.     

Investigations in the field of lipids

Summary 1. The synthesis of the following neutral plasmalogens has been effected: -O-(octadec-1-enyl)-, distearoylglycerol, -O-(octadec-1-enyl)-, -dipalmitoylglycerol, -O-(hexadec-1-enyl)-, -distearoylglycerol, and -O-(pentadec-1-enyl)-, -dipalmitoylglycerol.2. During the synthesis, the following compounds were isolated and characterized by their physicochemical constants: the -octadec-1-enyl ether of glycerol, -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, the tosylate of -(2-hydroxyoctadecyl) , -isopropylideneglyceryl ether, and -O-(2-tosyloxyoctadecyl) glycerol.3. The IR spectra of the -octadec-1-enyl ether of glycerol and the neutral plasmalogens have been studied.Khimiya Prirodnykh Soedinenii, Vol. 2, No. 6, pp. 367–371, 1966     

A new steroid glycoside from the starfishPatiria pectinifera

From the glycoside fraction of the starfishPatiria pectinifera, after its desulfation, an artefactural glycoside has been obtained: 29(-L-arabinofuranosyloxy)-5-stigmastane-3,6,8,15,16-pentaol (I). The structure of (I) was shown by¹H and¹³C NMR spectra and mass spectra and by acetylation and high-temperature hydrogenation.Pacific Ocean Institute of Bioorganic Chemistry, Far Eastern Scientific Center, Academy of Sciences of the USSR, Vladivostok. Institute of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 3, pp. 356–361, May–June, 1985.     

Chemistry of the lipids

Conclusions 1. A. new route for the synthesis of optically active ,-diglycerides has been developed.2. D- and L-, -Distearins and D-, -dilinolenin have been synthesized from the readily accessible L- and D--O-tritylglycerols.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 4, pp. 210–214, 1969