秦岭龙胆的化学成分

从秦岭龙胆(Gentiana apiata N.E.Br.)全草的乙醇提取物中分离得到4个化合物,通过波谱分析分别鉴定为异荭草甙(isoorientin),龙胆苦甙(gentiopicroside),asystasioside A和蔗糖(D-sucrose).采用二维NMR分析,确定了asystasioside A的立体结构.以上化合物均为首次从该植物中发现.     

Diphosphatetraazacycloogtatetraenes. I. Syntheses and properties

A series of novel eight-membered heterocycles containing 1,3 and 1,5 phosphorus arrangements were synthesized. The 1,5-diphosphatetraazacyclooctatetraenes were obtained from the interaction of perfluoroalkyletheramidines and trichlorophosphoranes; the 1,3-isomers were prepared from perfluoroalkyletherimidoylamidines and imido-tetraphenyl-diphosphinic acid trichloride. The two series of cyclooctatetraenes exhibited infrared spectral absorptions characteristic for the given positional arrangement. However, electron impact fragmentation patterns of the two ring systems were closely comparable.     

Triterpenoid saponins from Ilex mamillata C.Y. Wu ex C.J. Tseng

Two new triterpenoid saponins, ilemaminosides A and B (1 and 2) along with six known saponins (3-8) were isolated from 70% ethanolic extract of the leaves of Ilex mamillata C.Y. Wu ex C.J. Tseng. The new saponins were characterised as 3-O-α-L-arabinopyranosyl-ilexgenin B (1) and 3-O-β-D-glucopyranosyl-(1?→?3)-α-L-arabinopyranosyl-ilexgenin B (2). The structures of compounds 1 and 2 were elucidated on the basis of the chemical and spectroscopic methods, and the structures of known compounds were identified by comparison of their spectroscopic data with those reported in the literature. The compounds showed inhibitory activities in anti-inflammatory assay in?vitro with IC(50) values in the range 25.37-38.33?μg?mL(-1).     

A new aromatic glucoside from stem bark of Illicium difengpi K.I.B. et K.I.M.

A new aromatic glucoside, namely 4-methoxyphenyl-(6-deoxy-α-L-mannopyranosyl)-β-D-glucopyranoside (1), together with six known aromatic glucosides (2–7) were isolated from the stem bark of Illicium difengpi. The structures of these compounds were established by spectroscopic methods. The isolated aromatic glucosides were tested for anti-inflammatory activity. Compounds 1, 3 and 6 showed significant inhibitory effect on nuclear factor kappa B (NF-κB) in RAW 264.7 macrophages induced by lipopolysaccharide.     

Picrylamino-substituted heterocycles. IV. Pyrazoles

This paper describes the synthesis of various picryl- and picrylamino-substituted pyrazoles. These compounds were prepared by condensing the appropriate pyrazole or aminopyrazole with a picryl halide or picrylpyrazole. Some of these materials could be nitrated under carefully controlled conditions to the corresponding nitropyrazole derivatives. The products were identified by n.m.r. spectroscopy, and their crystal densities and thermal stabilities were determined. Drop-weight impact sensitivities were measured for some of the more interesting compounds.     

Two New C—glucoside Flavonoids from Leaves of Crataegus pinnatifida Bge. var. major N.E.Br.

Two new C-glucoside flavonoids,namely 8-C-β-D-（2″-O-acetyl) glucofuranosyl apigenin and 3″-O-acetylvitexin, were isolated from beaves of Crataegus pinnatifida Bge. var. major N.E.Br.Their structures were elucidated by the spectroscopic means and chemical evidence.     

Picrylamino-substituted heterocycles. II. Furazans

This paper describes the synthesis of the various picrylamino- and nitro-substituted furazans and bifurazanyls. Except for 3,4-bis(picrylamino)furazan, which was obtained by nitrating 3,4-dianilinofurazan, the picrylaminofurazans were prepared by condensing the appropriate amino-furazan with picryl fluoride in the presence of triethylamine. The various aminofurazans were oxidized with peroxytrifluoroacetic acid to the corresponding nitro derivatives.     

Legionella moravica sp. Nov. and Legionella brunensis sp. Nov. Isolated from cooling-tower water

Two Legionella-like organisms were isolated from cooling-tower water samples in Czechoslovakia. They were presumptively identified as legionellae by their growth on buffered charcoal-yeast extract agar (BCYE) containing L-cysteine and their absence of growth on BCYE without L-cysteine. Both strains contained predominantly branch-chained cellular fatty acids and were therefore definitively placed in the genus Legionella. They were serologically distinct from other described Legionella species and were shown by DNA studies to constitute two new Legionella species, Legionella moravica (type strain 316-36; ATCC 43877) and Legionella brunensis (type strain 441-1; ATCC 43878).     

Comparative gas chromatographic analysis of narcotics. III. Phenmetrazine hydrochloride.

Chemical signatures of phenmetrazine hydrochloride were studied by gas chromatography. The inter-batch variations of the signatures were found to be large whereas the intra-batch variations were usually small. The method is used for the tracing of seized phenmetrazine hydrochloride samples to common sources, which in turn may permit further tracing back to chains of illicit distribution of this drug. The applicability of the method to other narcotics is also discussed.     

Sulfur-containing polymers. VII. Alternating copolydisulfides

A variety of copolydisulfides have been synthesized in high yields by the fragmentation polymerization of bis(sulfenyl thiocarbonates) with dithiols in the presence of triethylamine. The structures of the copolymers were investigated by x-ray and NMR studies. Alkylene–arylene copolydisulfides were alternating. Alkylene–arylene copolymers derived from arylene dithiols were alternating, and those prepared from alkylene dithiols were generally random. It was concluded that the present procedure makes it possible to prepare various kinds of alternating copolydisulfides by using appropriate combinations of a bis(sulfenyl thiocarbonate) and a dithiol.     

Azidinium-Salze. 23. Mitteilung. Photolyse heterocylischer Azidinium-Salze

Photolysis of Heterocyclic Azidinium Salts The photochemistry of some azidinium salts was investigated. Their photolusis led to a large variety of products which were isolated and identified. Reaction mechanisms involving singlet and triplet nitrene intermediates are discussed to explain the product formation.     

Cyclopolymerization. XIII. Cyclopolymerization of Diallylaminomethylphenols

New highly substituted benzyl diallylamino monomers were prepared from substituted phenols by use of the Mannich reaction. Their ability to cyclopolymerize as the free phenols and the structures and properties of the pomers formed were investigated.     

Comparative gas chromatographic analysis of narcotics. II. Amphetamine sulphate.

Trace impurities in amphetamine sulphate were studied by a highly sensitive gas chromatographic method. The concentration of these impurities varied considerably between batches whereas the variations within the batches were usually very small. The method is used for the assignment of seizures of amphetamine sulphate to common sources, which in turn may permit chains of illicit distribution of this drug to be traced.     

珠子参化学成分分析

从珠子参根茎中分离得到7个化合物. 利用核磁共振、 质谱和红外等手段, 并结合其理化性质, 鉴定了其结构, 它们分别是24(R)-珠子参苷R1, 6-O-[β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃葡萄糖基(1→4)-β-D-吡喃葡萄糖基]-20(S)-原人参三醇、 6″-乙酰基-人参皂苷Rd、 人参皂苷Rf、 竹节参皂苷Ⅳa、 人参皂苷Rd和竹节参皂苷Ⅴ. 其中, 24(R)-珠子参苷R1和6-O-[β-D-吡喃葡萄糖基(1→2)-β-D-吡喃葡萄糖基]-20-O-[β-D-吡喃葡萄糖基(1→4)-β-D-吡喃葡萄糖基]-20(S)-原人参三醇为2个新化合物, 6″-乙酰基-人参皂苷Rd 和人参皂苷Rf为首次从珠子参根茎中得到.     

Densely crosslinked polycarbosiloxanes. I. Synthesis

Novel densely crosslinked polycarbosiloxanes were obtained by using functional branched prepolymers. Two types of soluble prepolymers were prepared from di- and trifunctional alkoxysilane monomers via cohydrolysis/condensation and for both final crosslinking occurred via hydrosilylation. The prepolymers having only vinyl functionalities (poly[phenylmethylvinyl]siloxanes, system A) were crosslinked by using a crosslinking agent with reactive silicon–hydrogen bonds. In the prepolymers having both silicon–vinyl and silicon–hydrogen functionalities (poly[phenylmethyl-vinylhydro]siloxanes, system B) crosslinking took place intermolecularly. For the characterization of the prepolymers ¹H-NMR, ²⁹Si–NMR, FT–IR spectroscopy, analytical SEC and VPO were employed. The prepolymers were fractionated with preparative SEC and the fractions analyzed with ¹H-NMR and analytical SEC. The crosslinking reaction was followed by FT–IR spectroscopy. The polymer networks were fully transparent homogeneous materials and are promising for future optical applications. © 1997 John Wiley & Sons, Inc.     

Thermoplasticization of wood. II. Cyanoethylation

Cyanoethylation was attempted to convert wood into thermoplastic material as a means to utilize low quality wood species as well as wood waste materials. Cyanoethylation reaction was conducted with control of the alkalinity of the reaction media, reaction temperature and time, and wood-to-acrylonitrile ratio. Cyanoethylated wood was purified and its nitrogen content and weight gain were determined. Fourier transform infrared (FTIR) spectroscopy was used to monitor the absorption peak of cyano group. Thermoproperties of cyanoethylated wood were analyzed by means of a differential scanning calorimeter (DSC) and a dynamic mechanical thermal analyzer (DMTA). Reaction mechanisms and chemistry influencing the thermoproperties of cyanoethylated wood were discussed.     

P-N compounds. 30. Phosphaminimides. 5. N-phosphinylimino-1,2,5,6-tetrahydropyridines

N-[ (Diethoxyphosphinyl)imino] and N-[ (diphenylphosphinyl)imino]-5-methyl-1,2,5,6-tetrahydropyridines were prepared by sodium borohydride reduction of the corresponding pyridinium and 3-methyl pyridinium inner salts. The carbonyl analog of this latter precusor was resynthesized and its structure completely verified.     

Gas chromatographic retention of carbohydrate trimethylsilyl ethers. IV. Disaccharides.

Trimethylsilyl ethers of seventeen disaccharides were injected on two stationary phases and their retention indices were calculated. Multiple linear regression was used to discuss relationships between retention indices and structural features of disaccharides.     

Carborane polymers. IV. Polysiloxanes

Carboranes attached to silicon through straight-chain alkyl groups were prepared and characterized for thermal stability by TGA and molecular weight change on heating. The monomers for these polymers were prepared generally by platinum-catalyzed addition of a silylhydride to an alkenyl or dialkenyl carborane. Polymerization was effected by hydrolysis-condensation of chlorosilanes, ring opening of cyclosiloxanes, and condensation of alkoxy and chlorosilanes. Two types of polymer structures were prepared, one contained m-carborane in the chain backbone, the other contained o-carborane as pendant alkylcarborane groups. Both types were obtained as elastomers; however, higher proportions of carborane in the polymers reduced elasticity and finally resulted in nonelastomers. TGA of the backbone carborane siloxane polymer indicated degradation at 370°C. in nitrogen and at 235°C. in air. Chain scission, as determined by molecular weight decrease, was observed on heating in nitrogen at 350°C. TGA of the pendant carborane siloxane polymer indicated that degradation in nitrogen and in air occurred at greater than 400°C. However, chain scission, as determined by molecular weight decrease, was observed upon heating at 300°C. in nitrogen.     

Pyrylocyanines. 29. tert-Butyl-substituted benzopyrylocyanines

2-tert-Butyl-4-methyl- and 2-methyl-4-tert-butylbenzopyrylium salts, as well as the sulfitr analog of the latter, were synthesized. Polymethine dyes with symmetrical and unsymmetrical structures were obtained from these salts. The factors that affect the color are analyzed.See [1] for Communication 28.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 339–344, March, 1992.