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.     

Aristoserratin,ein neues Indolalkaloid aus Aristotelia serrata W.R.B. OLIVER und A. peduncularis (LABILL.) HOOK. F. 178. Mitteilung über organische Naturstoffe

Aristoserratine, a New Indole Alkaloid from Aristotelia serrata W.R.B. OLIVER and from A. peduncularis (LABILL .) HOOK . F. The new indole alkaloid aristoserratine (2) has been isolated from Aristotelia. Its structure and absolute configuration were elucidated on the basis of spectroscopic data.     

Cover Picture: Angew. Chem. Int. Ed. 12/2002

The cover picture shows the thermally induced shape‐memory effect for a covalently cross‐linked polymer network. The polymer in its temporary shape (cube, picture on top) is heated from room temperature up to 70°C. Within 60 seconds the sample recovers its memorized, permanent shape of a nearly planar foil (picture on top left). The visual change of the material from opaque to transparent is caused by the melting of crystallites of the switching segments. The scheme in the center of the picture illustrates the molecular mechanism of the shape‐memory effect. The shown polymer network, which is synthesized from poly(ε‐caprolactone)dimethacrylate as macromonomer, is one of the first polymer systems that have specifically been developed for applications in the biomedical field. The net points (black) determine the permanent shape while the crystallites (blue) stabilize the temporary shape. More on the current state and the potential of this technology can be found in the review by A. Lendlein and S. Kelch on p. 2034 ff.     

Alkaloids ofHaplophyllum foliosum. II.

In addition to the alkaloids known previously from this plant, haplofoline and folifine, from the epigeal part ofHaplophyllum foliosum we have isolated norgraveoline with mp 288–289°C (decomp. from acetone), and myrtopsine with mp 201–202°C (from chloroform), [α]_D-5° (c 0.05; methanol), which were first obtained fromHaplophyllum dubium andMyrtopsis sellingii, respectively. We have confirmed by the PMR-spectroscopic method the positions of the substituents in the dihydrofuran ring of myrtopsine suggested previously on the basis of biogenetic considerations. In addition, it has been established that the substituents are present in the trans form. This is the first time that myrtopsine has been detected in plants of the genusHaplophyllum.     

Pyrimidines. 73. Synthesis of acetylpyrimidines

It is shown that the use of benzene as the solvent in the preparation of 2- and 4-acetylpyrimidines from cyanopyrimidines via the Grignard reaction makes this reaction a practical method for the preparation of pyrimidinyl ketones. Preparatively convenient methods for the preparation of 4-acetylpyrimidine from 4-ethylpyrimidine through the -oximino derivative and 5-acetylpyrimidine from 4,6-dichloro derivatives of pyrimidine are proposed.See [1] for communication 72.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 958–962, July, 1981.     

Silicon-29 and carbon-13 n.m.r. studies of organosilicon chemistry. VII—trimethylsilylated silicates

Silicon-29 n.m.r. was used to study the products from trimethylsilylation of minerals. Chemical shifts are reported for four model compounds, viz. the monomer, dimer, linear trimer (from natrolite) and cyclic tetramer (from laumontite). Information is then obtained from the products of trimethylsilylation of the anhydrous calcium silicates wollastonite and pseudo-wollastonite. In the latter case it is shown that the principal products are the four model compounds, and percentage yields are obtained for these.     

Magnetic Recording of N.Q.R. spectra

This paper gives complete details of a unique system for Magnetically Recording the Analogue Spectral Signals from an N.Q.R. Spectrometer of the S.R.O./Marginal Oscillator type.This is a very low cost system, but producing a very high order of play-back resolution from recordings, using a normal domestic Cassette or Tape, Reel to Reel Recorder. Spectra can also be transmisted via telephone lines, fibre optic links or radio frequencies.This system has been used now for several years, and due to the design being based mainly om passive components, the order of reliability is extremely high, without any faults being encountered to dete!.     

Triaziridine. 9. Mitteilung. Ringöffnungen von Triaziridinen

Triaziridines. Ring Openings of Triaziridines Eleven triaziridine derivatives were heated at 60° in CDCl₃ to obtain information on the tendency towards, resp. the resistance to, ring opening of the N₃-homocycle by thermolysis. Among these triaziridines, there are three which contain, as one of the substituents, a methoxycarbonyl group (ester derivatives 1 , 5 and 16 ), three a methyl group (methyl derivatives 18 , 24 , and 26 ), three an H-atom ( 14 , 27 , and 30 ), and two a negative charge ( 31 and 32 ). The other two substituents in each of these four classes of triaziridines are trans-located i-Pr groups ( 1 , 18 , 27 , and 31 ), cis-located i-Pr groups ( 5 , 24 , 14 , and 32 ), and a 1,3-cis-cyclopentylidene group ( 16 , 26 , and 30 ). As major products these mild thermolyses, we isolated : from the trans-ester 1 and from the annellated ester derivative 16 , the 1-acyl-azimines 2 and 17 , respectively, from the cis-ester 5 , the 3-acyl-triazene 4 , from the trans-methyl derivative 18 , the (E)-diazene 19 , and hexamine 21 , from the cis-methyl derivative 24 the 2-methylazimine 25 , both from the trans- and cis-H-derivatives 27 , and 14 , respectively, the H- triazene 13 and, finally, both from the trans-and cis-anion 31 and 32 , respectively – after protonation the H-triazene 13 and – after methylation – the methyl-triazene 33 . The same thermolysis of the annellated methyl and H-derivatives 26 and 30 , respestively, resulted only in decomposition. These results can be uniformly interpreted with a primary opening of the triaziridine ring by rupture of one of the two types of N? N bonds lending to azimines or triazenide anions. Some of the azimines were isolable, namely 2 , 17 , and 25 , and one was spectroscopically observable as an intermediate, namely 11 on the way to the triazene 4 . The other azimines are plausible intermediates to the isolated products, namely 15 on the way to 13 , and 22 on the way to 19 and 21 . The triazenide anion 28 is the evident intermediate on the way to 13 or to 33 . The annellated azimines are assumed not be formed from 26 and 30 , or then to be be decomposed under the conditions of their formation. We conclude that the triaziridine derivatives 1, 16 , and 18 underwent thermal ring opening between N(1) and N(2), while the derivatives 5 , 14 , 24 , 27 , 31 , and 32 were ruptured between N(2) and N(3); no conclusion was possible on the ring opening of the derivatives 26 and 30 . The predominant formation of the (Z)-azimine 2 from the trans-triaziridine 1 , and of the (E)-isomer 3 – among the two azimines – from the cis-triaziridine 5 suggests a stereospecificity in the triaziridine ring openings. This would, however, not be expected to be observable in the products from the other triaziridines, since both N? N bonds of the azimine 25 and of the anion 28 probably rotate rapidly and since the secondary trans formations of the other primary products are not able to retain configurational information.     

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.     

Experimental Resolution and Brand Profile in F.T.-I.R. Spectroscopy

The minimum possible number of sampling points (N) to achieve rapid and accurate scan and the best I.R.-F.T. spectra in terms of resolution, height (H) half height band width (HH) are discussed. The experimental resolution, for a particular number of data points, was measured from the distance of any newly evolved peak from its closest neighbor when increasing N in a water vapour interferogram; the experimental curve is close to the theoretical one. H and HH of any peak are found to increase and decrease respectively when the optical path is enlarged up to a certain limit and thereafter, they become almost constant. Taking informations with further values of N merely adds noise with no sign of improvement in the spectra.     

Berberis alkaloids. XV. Structure of bargustanine

Bargustanine (I), belonging to a new type of isoquinoline alkaloids, has been isolated from the phenolic fraction of the total alkaloids from the roots ofBerberis vulgaris L. Its structure has been established by chemical and spectral methods.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences, Tashkent. Andizhan State Medical Institute. Translated from Khimiya Prirodnykh Soedinenii, No. 1, pp. 44–47, January–February, 1993.     

Aromatic annelation. I. Synthesis of pyridines.

The preparation of substituted pyridines from cycloalkanones by elaboration of an aromatic ring is described.     

Dihydropyridazines. III . Reactions with oxygen

The reactions of oxygen with a series of dihydropyridazines have been explored. The primary reaction other than aromatization appears to occur from the 1, 4-dihydro tautomer. A single crystal x-ray structure has been determined on the product from the reaction of oxygen with 3, 6-diphenyl-4, 4-dimethyl-1, 4-dihydropyridazine.     

Berberis alkaloids. XXIII. Structure of turcberine

Berberine, magnoflorine, palmatine, columbamine, jatrorhizine, epiberberine, berbamine, O-methylisothalicberine, armepavine, corypalline, glaucine, and corydine and the new alkaloid turcberine have been isolated fromBerberis turcomanica Kar., and the structure of turcberine has been established. Apart from berberine, this is the first time that any of these alkaloids have been isolated from this species of barberry, while this is the first time that corydine and armepavine have been isolated from the genusBerberis.Institute of Chemistry of Plant Substances, Uzbekistan Republic Academy of Sciences. Tashkent. Andizhan State Medical Institute. Translated from Khimiya Prirodnykh Soedeninii, No. 1, pp. 77–81, January–February, 1993.     

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.     

Donor-Acceptor Complexes in Copolymerization. LIX. Alternating Diene-Dienophile Copolymers. 13. Copolymerization of Dicyclopentadiene and Maleic Anhydride

The solution and bulk copolymerization of dicyclopentadiene (DCP) and maleic anhydride (MAH) occurs over the temperature range 80–240°C, upon the addition of a free-radical catalyst which has a short half-life at the reaction temperature. An unsaturated 1/1 MAH/DCP copolymer, derived from the copolymerization of MAH with the norbornene double bond, followed by a Wagner-Meerwein rearrangement, is obtained in the presence of a large excess of DCP at 80° C, while a saturated 2/1 MAH/ DCP copolymer, derived from the cyclocopolymerization of the residual cyclopentene unsaturation, is obtained at higher temperatures or in the presence of excess MAH. The copolymers prepared under other conditions with intermediate MAH/DCP mole ratios contain both 1/1 and 2/1 repeating units. The copolymer obtained from bulk copolymerization above 170° C contains units derived from cyclopentadiene-MAH cyclocopolymerization as well as DCP-MAH copolymerization.     

Aromatic Annelation. II. Synthesis of phenols.

The preparation of substituted phenols from cycloalkanones by elaboration of an aromatic ring is described.     

1,2-Epoxycarotinoide. 3. Mitteilung. Isolierun von 1,2-Epoxy-1,2-dihydrolycopin aus Tomaten

1,2-Epoxycarotenoids: Isolation of 1,2-Epoxy-1,2-dihydrolycopene from Tomatoes The optically active, 1,2-epoxy-1,2-dihydrolycopene was isolated from tomatoes. Its constitution was established by comparison with the racemic synthetic compound.     

Indole derivatives. 126. Substituted nitrotryptamines

A preparative method has been developed for obtaining substituted nitrotryptamines from the corresponding nitrophenylhydrazones of -phthalimidobutyraldehyde.For communication 125, see [1].Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 9, pp. 1206–1210, September, 1984.     

Pyrylocyanines. 10. Isobenzothiopyrylocyanines

Polymethine dyes with symmetrical and unsymmetrical structures and 3-phenyl-2-benzothiopyrylium derivatives were synthesized. The color of these dyes is discussed. See [1] for communication No. 9. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 777–782, June, 1980.