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1.
The acetylenic diol 2 , prepared by reaction of but-3-yn-2-ol dianion with 2,6,6-trimethyl-4,4-ethylenedioxy-cyclohex-2-en-1-one ( 1 ), afforded 3,5,5-trimethyl-4-(2-butenylidene)-cyclohex-2-en-1-one ( 4 ), a major constituent of Burley tobacco flavour, upon LiAlH4 reduction and hydrolysis. Vomifoliol ( 5 ) and blumenol C ( 6 ) were major by-products in this reaction. 相似文献
2.
The benzazepin-2-ones 7 and 9 were prepared from homoveratroyl chloride (4) and phenacylamine. Compounds 7 and 9 were used for the preparation of the benzazepin-2-amines 3, 11, 13 and 14. A synthesis of the benzazepine-1,2-dione 17 and the benzazepine-2,4-dione 20 is also described. 相似文献
3.
Two novel constituents of Burley tobacco condensate were shown to be 5-(4-methyl-2-furyl)-6-methylheptan-2-one (solanofuran, 4 ) and 3,4,7-trimethyl-1,6-dioxa-spiro[4.5]-dec-3-en-2-one (spiroxabovolide, 6 ). These structures were deduced from spectral data and confirmed by synthesis. Solanofuran ( 4 ) was prepared via the dye-sensitized photo-oxygenation of solanone ( 1 ). This type of reaction involving the uncommon ‘diene-addition’ of 1O2 to a conjugated acyclic diene system was thus applied for the first time to the synthesis of a terpenoid furan, a route that might have some biogenetic significance. Both solanofuran ( 4 ) and spiroxabovolide ( 6 ) display interesting organoleptic properties. Identification of these compounds increases to 210 the total number of Burley tobacco flavour constituents so far characterized in this laboratory. 相似文献
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The synthesis of 5,6-dihydro-1H,3H-pyrrolo[3,2,1-ij][3,1]benzoxazine-1,3-dione ( 2a ), a new ring system, from N-acetylindoline is described. 相似文献
6.
标题化合物C24H30O5是由邻甲氧基苯甲醛与5,5-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得。结构通过单晶X-射线衍射法确定,其晶体属于单斜晶系,空间群C2/c,a=33.942(6),b=7273(1),c=22667(4)A,β=128.989(9)°,Mr=398.50,V=4349(1)A3,Dc=1.2179·cm-3,Z=8,μ(MoKa)=840mm-1,F(000)=1712。晶体结构用直接法解出,经用全矩阵最小二乘法对原子参数进行修正,最后的偏离因子为R=0.043,Rw=0.052。在晶体结构中,存在一个分子间氢键。 相似文献
7.
Investigation by gas liquid chromatography of a small but organoleptically typical subfraction of Oriental tobacco condensate led to the identification of 47 compounds. Of these 21 have hitherto not been reported as Oriental tobacco constituents, and 14 appear to be novel to all tobacco types. The latter are (E)-3-methyl-non-2-en-4-one ( 1 ), (E)-1-(2, 3, 6-trimethylphenyl)-but-2-en-1-one ( 3 ), pentadecan-15-olide ( 12 ), 8α, 13:9α, 13-diepoxy-15, 16-dinorlabdane ( 17 ), (Z)-octadec-9-en-18-olide ( 18 ), (E)-2-ethylidene-6, 10, 14-trimethylpentadecanal ( 21 ), the norlabdanoids 9 , 10 , 11 , 14 , 15 , 16 , tridecan-2-one, and 2-phenylethyl isovalerate. The macrolides 12 and 18 represent the first musk compounds detected in tobacco. Identification were made by direct comparison (MS. and/or 1 H-NMR./IR.) with the authentic chemicals synthesized whenever necessary. 相似文献
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3, 5, 6-哌嗪三酮-2-甲酰胺(5)经与PCl5-POCl3反应制得3, 5, 6-三氯-2-氰基吡嗪(6)。6经转化为甲酯(7)再水解为3, 5, 6-三氯-2-吡嗪甲酸(8)。由8出发合成了两个2, 3-二氯-5-取代-5, 8-二氢-8-氧-吡啶并[2, 3-b]吡嗪-7-羧酸乙酯(11a~b)。其中5, 7~11均为新化合物, 其组成和结构经元素分析、IR、^1H NMR、MS证实。 相似文献
10.
N-Bromoacetyl-2-vinylpyrrolidine underwent cyclization to give a pyrrolizidine derivative in the presence of a base and a catalytic amount of palladium catalyst. 相似文献
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通过2-甲基-4-对甲苯基-1-苯甲酰基-2,3-二氢-1H-1,5-苯并二氮杂与由不对称1-苯基-2-偶氮-1,3-丁二酮热解产生的a-羰基烯酮的[2+4]环加成反应制备了标题化合物(C34H30N2O3,Mr=514.62),用X射线衍射测定了其单晶结构。晶体属单斜晶系,空间群为P21/n,a=11.560(1),b=19.058(3),c=13.207(2)A,β=106.82(1)°,V=2785.2(7)A3,Z=4,Dc=1.230g.cm-3,MoKa(λ=0.71073A),μ=0.064mm-1,F(000)=1088,2278个可观测衍子射点,R=0.046,Rw=0.049。分子骨架为由苯环、具有类扭船式构象的七元二氮杂环和略微扭曲的唑酮环构成的三环体系。 相似文献
12.
Twelve novel constituents isolated from Burley tobacco condensate by semi-preparative GLC. have been identified as (E)-3,4-epoxy-5-isopropyl-nonane-2,8-dione ( A ), exo-(1-methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]oct-6-yl)methyl ketone ( B ), exo-1-(1-methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]oct-6-yl)-ethanol ( C ), (E)-5-isopropyl-8-hydroxy-8-methyl-non-6-en-2-one ( D ), (E)-5-isopropyl-6,7-epoxy-8-hydroxy-8-methyl-nonan-2-one ( E ), endo-2-(1-methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]oct-6-yl)-propan-2-ol ( F ), 3,3,5-trimethyl-8-isopropyl-4,9-dioxabicyclo[3.3.1]nonan-2-ol ( G ), (E)-5-isopropyl-non-3-ene-2,8-diol ( H ), 5-isopropyl-nonane-2,8-diol ( I ), (E)-5-isopropyl-8-hydroxy-non-6-en-2-one ( J ), 5-isopropyl-8-hydroxy-nonan-2-one ( K ), and (E)-3-isopropyl-6-methyl-hepta-4,6-dien-1-ol ( L ). Compounds A–K were synthesized from norsolanadione ( 2 ), and compound L from 2-isopropyl-5-oxo-hexanal ( 15 ). The relative configuration of the bicyclic internal acetals B, C, F, G and their δ-keto-epoxide precursors A and E is discussed. All these Burley tobacco flavour components belong to a growing family of metabolites structurally related to solanone ( 1 ). They are believed to arise from the breakdown of cembrene-type precursors. 相似文献
13.
The Biginelli reaction between 5-R-salicylic aldehyde (R = H, Me, and Br), α-nitroacetophenone, and urea affords 8-R-11-nitro-2-phenyl-5,6-dihydro-2H-2,6-methanobenzo-[g][1,3,5]oxadiazocin-4(3Н)-ones as mixtures of two diastereomers. The ratio of diastereomers depends on the catalyst (HCl) concentration in the reaction medium. In DMSO and DMF, the resulting compounds undergo oxadiazocine ring opening with establishment of a three-component equilibrium between 4-(2-hydroxy-5-R-phenyl)-5-nitro-6-phenyl-3,4-dihydropyrimidin-2(1Н)-one as the major component and diastereomeric methanobenzoxadiazocines as two minor components. Dilution of these solutions with water favors the oxa-Michael reaction resulting in the reverse transformation of dihydropyrimidinones into the corresponding starting diastereomers. 相似文献
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15.
A synthesis of novel derivatives of 6-methyluracil, 6-methyl-2-thioxo-, and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one
containing a 2-(phenoxy)ethyl substituent at position 5 of the pyrimidine ring has been carried out. It was found that 5-[2-(phenoxy)ethyl]
derivatives of 6-methyl-2-thioxo- and 2-imino-6-methyl-2,3-dihydro-1H-pyrimidin-4-one are obtained by the condensation of
the corresponding ethyl 3-oxo-2-(2-phenoxyethyl)butanoates with thiourea or guanidine. 6-Methyl-5-[2-(phenoxy)ethyl]uracils
can be prepared by treating 6-methyl-5-[2-(phenoxy)ethyl]-2-thioxo-2,3-dihydro-1H-pyrimidin-4-ones with an excess of aqueous
monochloroacetic acid solution.
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Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1213–1217, August, 2005. 相似文献
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A. C. Schroeder T. Srikrishnan R. Parthasarathy A. Block 《Journal of heterocyclic chemistry》1981,18(3):571-574
Reaction of 2-amino-3′,5′-bis(O-tert-butyldimethylsilyl)-β- D -arabinofuran[1′,2′:4,5]-2-oxazoline with 2-chloroethylsulfonyl chloride in the presence of sodium bicarbonate followed by removal of the protecting groups gave 2′,3-anhydro-4-β- D -arabinofuranosyl-5,6-dihydro-2H-1,2,4-thiadiazin-3-one 1,1-dioxide ( 5 ), which by treatment with ammonia was converted to 4-β- D -arabinofuranosyl-5,6-dihydro-2H-1,2,4-thiadiazin-3-one 1,1-dioxide ( 6 ). The structure of compound 5 was unequivocally established by means of an x-ray diffraction analysis. The compound crystallized in the space group P212121 with unit cell dimensions a = 5.883(3), b = 9.352(2), c = 18.769(7) Å, Z = 4. Its structure was established by direct multisolution techniques and refined by the full matrix least squares method to a final R value of 0.058 for the 1515 reflections observed. 相似文献
19.
The Claisen-Schmidt condensation between 1,2-dihydro-11-(trifluoromethyl)-3H,7H-quino-[8,1 -cd][1,5]benzoxazepin-3-one, 1 , and aromatic aldehydes has been investigated. The acid catalyzed reactions yielded the trans-2-benzylidene derivatives, 4 ; the structures and configurations of the group of compounds represented by 4 have been confirmed by pmr in conjunction with the Eu(fod)3 shift reagent. In contrast, catalysis with sodium hydroxide gave the isomeric 2-benzyl-endocyclic α,β-unsaturated ketones, 3. Finally, the 4 could be isomerized to the corresponding 3 by means of sodium hydroxide. The ir, uv, and pmr spectra of these compounds are discussed. 相似文献