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1.
Reaction of readily available 2-methyl-4-formylthiazole ( 1 ) with glyoxal and ammonia gave 2-(2-methyl-4-thiazolyl)imidazole ( 2 ). Nitration of 2 with a mixture of nitric acid-sulfuric acid at 100° yielded 2-(2-methyl-4-thiazolyl)-4,5-dinitroimidazole ( 3 ) as the sole reaction product, while nitration at 65° afforded 2-(2-methyl-4-thiazolyl)-4-(or 5)-nitroimidazole ( 4 ). N-Methylation of compound 4 in the presence of base gave 1-methyl-2-(2-methyl-4-thiazolyl)4-nitroimidazole ( 6 ), whereas N-methylation with diazomethane afforded 1-methyl-2-(2-methyl-4-thiazolyl)-5-nitroimidazole ( 5 ). N-Methylation of compound 3 yielded 1-methyl-2-(2-methyl-4-thiazolyl)-3,5-dinitroimidazole ( 7 ) in high yield.  相似文献   

2.
Photolysis of N-benzyl-N-phenylearbamoylazide (IVc) afforded 1-benzy 1-2-benzimidazolinone (Ic), 2-benzimidazolinone (IIe), 4-benzy 1-2-benzimidazolinone (IIe), and 5-benzy1-2-benzimidazo-linone (IIf)- The same reaction of N-benzyl-N-(4-chlorophenyl) carbamoyl azide (IVd) gave 3-benzyl-1-(phenylhydrazocarbonyl)-2-benzimidazolinone (VIb) besides the above four products. In the case of N-benzyl-4-(4-butoxyphenyl)carbamoyl azide (IVe), 1-benzy1-5-butoxy-2-benz-imidazolinone (1e), 5-butoxy-2-benzimidazolinone (IId), 5-benzy1-2-benzimidazolinone (IIf), and 4-benzy1-6-butoxy-2-benzimidazolinone (IIg).  相似文献   

3.
Six new alkaloids, broussonetines W, X, M1, U1, J3, and J2 (1-6) were isolated from the branches of Broussonetia kazinoki SIEB. (Moraceae) as minor constituents. They were formulated as (2R,3R,4R,5R)-2-hydroxy-methyl-3,4-dihydroxy-5-17-(cyclohexy-2-on-1(6)-enyl)heptyllpyrrolidine (1), (2R,3S,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-17-(cyclohexy-2-on-1(6)-enyl)heptyl]pyrrolidine-4-O-beta-D-glucopyranoside (2), (2R,3R,4R,5R)-2-hydroxymethyl-3,4-dihydroxy-5-[(9R)-9,13-dihydroxytridecyl]- pyrrolidine (3), (2S,3S,4S)-2-hydroxymethyl-3,4-dihydroxy-5-(10-oxo-13-hydroxytridecyl)-5- pyrroline (4), (2R)-2-[(IS,2S)-1,2-dihydroxy-8-1(2R,3R,4R,5R)-5-(2-hydroxymethyl-3,4-dihydroxy-1-acetylpyrrolidinyl)loctyl]piperidine (5), (2R)-2-[(1S,2S)-1,2-dihydroxy-8-[(2R,3R, 4R,5R)-5-(2-hydroxymethy]-3,4-dihydroxypyrrolidinyl)]octyl]piperidine (6).  相似文献   

4.
Bovine β-1,4-galactosyltransierase is an efficient catalyst for the regioselective transfer of galactose from UPD-galactose, generated in situ with the UDP-glucose/UDP-glucose-4-epimerase system, to the kaurane glycosides stevioside ( 1 ) and Steviolbioside ( 2 ), affording the corresponding galactosyl derivatives 3 and 4 in high yields. By a combination of 2D NMR techniques (COSY, TOCSY, ROESY, HMQC, and HMBC), the structure of the products is established as 13-[(β -D -galactopyranosyl-(1 → 4)-β-D -glucopyranosyl-(1 → 2)- β -D -glucopyranosyl)oxy]kaur-16-en-19-oic acid β -D -glucopyranosyl ester ( 3 ) and 13-[(β-D -galactopyranosyl-(1 → 4)- β-D -glu-copyranosyl-(1 → 2)- β-D -glucopyranosyl)oxy]kaur-16-en-19-oic acid ( 4 ).  相似文献   

5.
Treatment of 1,2,5,6-tetrahydro-2-(4-hydroxy- and/or 4-methoxybenzyl)-3,4-dimethyl-I-(3-methyl-2-butenyl)pyridines (IV and V) and 2-(4-methoxybenzyl)-3,4-dimethyl-1-(3-methyl-2-butenyl)-4-piperidinol (X) with acid afforded 9-(4-hydroxy- and/or 4-methoxybenzyl)-4,4,5,6-tetramethyl-1-azabicyelo[3,3,1]non-6-ene (XIII and XIV). In contrast, the corresponding 1-allyl-substituted derivatives VI, VII, and XI were converted into the expected 3-allyl-1,2,3,4,5,6-hexahydro-8-hydroxy- and/or 8-methoxy-6,11-dimethyl-2,6-methano-3-benzazocine (II and III).  相似文献   

6.
4-Toluenesulfonyl isocyanate (I) reacted with 2-aminoethanol and 3-amino-l-propanol to give 2:1 isocyanate/amino alcohol addition products. 1-Amino-2-propanol and I gave 1:1 and 2:1 adducts while 2-amino-2-methyl-l-propanol afforded only a 1:1 adduct. 4-Toluenesulfonyl isothio-cyanate (III) gave 1:1 adducts with 2-aminoethanol, l-amino-2-propanol and 3-amino-l-propanol, the first two of which were cyclized by concentrated sulfuric acid to 1-(4-toluenesulfonyl)-imidazoline-2-thiones and the third to 1-(4-toluenesulfonyl)hexahydropyrimidine-2-thione. A 1:2 adduct was obtained from III and 2-amino-2-methyl-l-propanol. Amino acids reacted with I and with 4-chlorobenzenesulfonyl isocyanate (II) to give N-(arylsulfonyl)-N1-(carboxylic acid)-ureas. N-(4-Toluenesulfonyl)-N1-(acetic acid)-urea (XVI) was converted to the methyl ester (XIX) by concentrated sulfuric acid and methanol and to water-soluble unrecoverable products by sulfuric acid alone. Glycine and III gave N-(4-toluenesulfonyl)-N1-(acetic acid)-thiourea (XX) which was converted to the methyl ester (XXII) by concentrated sulfuric acid/methanol and to the cyclic 1-(4-toluenesulfonyl)imidazolin-5-one-2-thione (XXI) by sulfuric acid alone.  相似文献   

7.
4-Chlorobenzenesulfonyl isocyanate (I) reacted with 2-chloroethanol and 1-chloro-2-propanol to give, respectively, 2-chloroethyl 4-chlorobenzenesulfonyl carbamate (III) and 1-chloro-2-propyl 4-chlorobenzenesulfonyl carbamate (VI). The carbamates III and VI cyclized under the influence of pyridine to afford, respectively, 3-(4-chlorobenzenesulfonyl)oxazolidin-2-one (IV) and 3-(4-chlorobenzenesulfonyl)-5-methyloxazolidin-2-one (VII). The oxazolidin-2-ones were stable toward hydrochloric acid but hydrolyzed in 2M sodium hydroxide solution to N-(2-hydroxyethyl)-4-chlorobenzenesulfonamide (V) and N-(2-hydroxy-1-propyl)-4-chlorobenzene-sulfonamide (VIII), respectively. 4-Toluenesulfonyl isothiocyanate (II) reacted with 2-chloroethanol to give 2-chloroethyl 4-chlorobenzenesulfonyl thiocarbamate (IX), which was converted by pyridine to 3-(4-toluenesulfonyl)oxazolidine-2-thione (X).  相似文献   

8.
The acid-catalyzed reaction of 1-aryl-5-(2-dimethylaminovinyl)-1H-tetrazoles 2 with arylamines suitably functionalized in the ortho-position resulted in Z-configurated transamination products which were cyclized to novel 3-tetrazolylquinolines by the action of sodium ethoxide. Thus, on reacting 2 with 2-aminoacetophenone or 2-aminobenzophenone, respectively, the 2-[2-(1-aryl-1H-tetrazol-5-yl)vinyl-amino]aryl ketones 3a-g were obtained, the cyclization of which gave 4-substituted 3-(1-aryl-1H-tetrazol-5-yl)quinolines 4 . In the case of the transamination products 3h-1 , prepared from 2 and methyl anthranilate, the ring closure afforded 3-(1-aryl-1H-tetrazol-5-yl)-1H-quinolin-4-ones 5 . Starting from 2 and anthranilonitrile 4-amino-3-(1-aryl-1H-tetrazol-5-yl)quinolines 10 were obtained via the corresponding intermediates 9 .  相似文献   

9.
The reactions of 3-phenylsydnonyllithium with a variety of ketones to afford tertiary carbinols 4a-4i and their subsequent dehydration to 4-(3-phenylsydnonyl) alkenes 5a-5i are discussed. Among the alkenes, 2-[4-(3-phenylsydnonyl)]propene ( 5b ) and 1-[4-(3-phenylsydnonyl)]-1-cyclohexene ( 5i ) were photochromic. A Wittig reaction between ethyl-4-(3-phenylsydnonyl)-ketone and methylenetriphenylphosphorane afforded the photochromic 2-[4-(3-phenylsydnon-yl)]-1-butene(5j).  相似文献   

10.
Phosphorus-containing dendrimers 1-[G'(1)]-1-[G'(4)] (generation 1 to generation 4) possessing terminal aldehyde groups reacted with a variety of hydrazino compounds. Addition of hydrazine itself to 1-[G'(1)]-1-[G'(4)] afforded the corresponding dendrimers 2-[G(1)]-2-[G(4)] with hydrazono groups at the periphery. Addition of methylhydrazine to 1-[G'(1)], 1-[G'(4)] gave the dendrimers 3-[G(1)], 3-[G(4)]. A Schiff reaction between 1-[G'(1)]-1-[G'(4)] and 1-amino-4-(2-hydroxyethyl)piperazine led to dendrimers 5-[G(1)]-5-[G(4)] possessing up to 48 alcohol chain ends. Treatment of 1-[G'(1)], 1-[G'(3)] with fluorenone hydrazone gave rise to macromolecules 7-[G(1)], 7-[G(3)] while the reaction of 1-[G'(1)], 1-[G'(2)], 1-[G'(4)] with 4-aminobenzo-15-crown-5 afforded the macromolecules 9-[G(1)], 9-[G(2)], 9-[G(4)] in which up to 48 crown ether units are anchored on the surface. Wittig reactions between 1-[G'(1)]-1-[G'(4)] with (acetylmethylene)triphenylphosphorane (10) or (cyanomethylene)triphenylphosphorane (12) allowed the formation of dendrimers 11-[G(1)]-11-[G(4)] or 13-[G(1)], 13-[G(4)] with alpha,beta unsaturated ketones or cinnamonitrile units, respectively, on the surface. Disubstitution of terminal P(S)Cl(2) groups of dendrimers 1-[G(1)]-1-[G(7)] with allylamine, propargylamine, or N-(trimethylsilyl)imidazole easily occurred to give macromolecules 14-[G(1)]-14-[G(7)], 15-[G(1)], 15-[G(4)], 16-[G(1)], 16-[G(4)].  相似文献   

11.
Facilitated SO4(2-) transfers by hydrogen bond-forming ionophores are investigated across the nitrobenzene (NB)-water interface by using polarography with a dropping electrolyte electrode. Bis-thiourea 1, alpha,alpha'-bis(N'-p-nitrophenylthioureylene)-m-xylene, is found to significantly facilitate the transfer of the highly hydrophilic SO4(2-) whereas its counterpart, N-(p-nitrophenyl)-N'-propylthiourea (ionophore 2), cannot. In contrast to the predominant formation of a 1:1 complex with SO4(2-) in the bulk NB phase, the SO4(2-) transfer assisted by 1 is indeed based on the formation of a 1:2 complex between SO4(2-) and ionophore, even under the condition of [SO4(2-)]aq > [1]org. Such an exclusive formation of the 1:2 (SO4(2-) to ionophore) complex at the NB-water interface is not observed with structurally similar bis-thiourea 3, alpha,alpha'-bis(N'-phenylthioureylene)-m-xylene, where p-nitrophenyl moietes of bis-thiourea 1 are simply replaced by phenyl groups. The facilitated transfer of SO4(2-) with bis-thiourea 1 is further compared to that of HPO4(2-) and H2PO4- across the NB-water interface, which was previously shown to be assisted by 1 through the formation of the 1:1 and 2:1 (anion to ionophore) complexes, respectively. On the basis of these examinations, unique binding behaviors of hydrogen bond-forming ionophores at the NB-water interface are discussed, with a view towards development of ionophore-based anion-selective chemical sensors.  相似文献   

12.
We synthesized useful intermediates 5 and 6 for 1 beta- and 1 alpha-methylcarbapenems from 4-carboxy-3-[(R)-1-hydroxyethyl]-2-azetidinone 4 as a starting material by using stereoselective hydrogenation and hydroboration, respectively. A practical synthetic route from 4 to the (3S,4S)-4-[(R)-1-carboxyethyl]-3-[(R)-1-hydroxyethyl]-2-azetidinone derivative 1, a useful intermediate for the synthesis of 1 beta-methylcarbapenem antibiotics, was established.  相似文献   

13.
Preparation and biological activity of the metabolites of the potent antihyperglycemic and antihyperlipidemic agent, (E)-4-(4-[(5-methyl-2-phenyl-1,3-oxazol-4-yl)methoxy]benzyloxyimino)-4-phenylbutyric acid (TAK-559) (1), were investigated. Metabolites M-I (2), M-II (3), M-III (4) and M-IV (5) were synthesized and their biological activities were evaluated by in vitro and in vivo experiments. Compounds 2-4 activate human peroxisome proliferator-activated receptor gamma one (hPPARgamma1) and hPPARalpha, but their activities are weaker than those of TAK-559 (1). Compound 5 only activates hPPARgamma1 weakly. TAK-559 (1) showed potent in vivo plasma glucose and triglyceride lowering activities in Wistar fatty rats after intraperitoneal administration, while its metabolites (2-5) showed comparatively weak activities.  相似文献   

14.
Investigation on the leaves of Melicope bonwickii (F.Muell.) T.Hartley (Rutaceae) afforded a new 7-(2'-hydroxy-3'-chloroprenyloxy)-4-methoxyfuroquinoline (1) together with the known 7-(2',3'-epoxyprenyloxy)-4-methoxyfuroquinoline (2), evellerine (3) kokusaginine (4) and an amide aurantiamide acetate (5). Compounds 1 and 2 showed significant activity against cervical cell lines (Hela).  相似文献   

15.
The synthesis of 3-(1H-imidazol-1-yl)-4H-1-benzopyran-4-ones 2 and of 2-(1H-imidazol-1-yl)-4H-1-benzopyr-an-4-ones 11 are described. The former proceeds through chroman ring closure from 2-(1H-imidazol-1-yl)-2′-hydroxyacetophenones, the latter occurs reacting 3-bromo-4H-1-benzopyran-4-ones with imidazole and represents an example of a new synthesis of 2-heteroarylchromones. Compounds 2 can be easily reduced to the corresponding chromanones and chromanols previously described in Part 1.  相似文献   

16.
Coeloglossum viride (L.) Hartm. var. bracteatum (Willd.) Richter is a plant of the Orchidaceae family, distributed in the Xinjiang, Inner Mongolia, Gansu and Qinghai provinces of China1. Its dried rhizomes have been used as a tonic in chinese folk medicine2. No chemical constituent is reported from this plant. The present paper deals with the isolation and structural elucidation of two new isobutyltartrate monoesters, named coelovirin A 1 and B 2. The ethanolic extract of the air-drie…  相似文献   

17.
Novel 1,4-dihydropyridine derivatives bearing 3-[4-(substituted amino)phenylalkyl]ester side chains were prepared and tested for their antihypertensive activity in spontaneously hypertensive rats. Most compounds showed a more potent antihypertensive effect and a longer duration of action than nicardipine. The derivatives with a benzhydrylpiperazinyl and a benzhydrylpiperidinyl group were distinctive. 2-[4-(4-Benzhydryl-1-piperazinyl)phenyl]ethyl methyl 1,4-dihydro-2,6-dimethyl-4-(3-nitrophenyl)-3,5-pyridinedicarboxylate (4e), its 4-(4-cyano-2-pyridyl) analogue (4f), its 3-[4-(4-benzhydryl-1-piperazinyl)phenyl]propyl ester analogue (4h), its 2-[4-(4-benzhydryl-1-piperidinyl)phenyl]ethyl ester analogue (4j), and its 2-[4-(1-benzhydryl-4-piperidinyl)phenyl]ethyl ester analogue (4k) were selected as candidates for further pharmacological investigations.  相似文献   

18.
A new ganglioside molecular species, HPG-7 (1) was obtained from the polar fraction of the chloroform/methanol extract of the sea cucumber, Holothuria pervicax. On the basis of chemical and spectroscopic evidence, the structure of 1 was determined, and the major component was 1-O-[alpha-L-fucopyranosyl-(1-->4)-(N-acetyl-alpha-D-neuraminosyl) - (2-->11)-(N-glycolyl-alpha-D-neuraminosyl)-(2-->4)-(N-acetyl -alpha-D- neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-(2S,3S,4R)-2-[(2R)-2- hydroxytetracosanoylamino]-14-methyl-hexadecane-1,3,4-triol. This is the first report on the isolation and structure elucidation of trisialo-ganglioside from sea cucumber. 1 showed neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cell.  相似文献   

19.
Reactions of 2-(4′-fluorophenyl)imidazole ( 1 ) and related compounds under various nitrating conditions are discussed. With 90% nitric acid in 20% oleum at ?10°, 1 affords 2-(4′fluorophenyl)-4(5)-nitroimidazole ( 2 ) in 80% yield. Reaction of 2 with the same reagents at 25° affords 2-(4′-fluoro-3′-nitrophenyl)-4(5)-nitroimidazole ( 4 ) in 90% yield, whereas with 90% nitric acid in acetic acid at 95°, 2 affords 4,5-dinitro-2-(4′-fluorophenyl)imidazole ( 5 ) in 80% yield. Reaction of 1 with 70% nitric acid in concentrated sulfuric acid at 25° affords 2-(4′-fluorophenyl)-5-hyroximinoimidazolin-4-one ( 6 ), which rearranges and hydrolyzes to 5-(4′-fluorophenyl)-1,2,4-oxadiazole-3-carboxylic acid. A discussion of these reactions is presented.  相似文献   

20.
The crystal structures of 1-(1-adamantyl)-3,5-dimethylpyrazole 1 and 1-(1-adamantyl)-3,4,5-trimethylpyrazole 2 were studied by X-ray analysis. The space groups and cell parameters are: 1 , Cc, 13.4452(4), 14.9407(4), 7.1119(2) Å, 90, 111.944(2), 90°, with Z = 4. 2, P21/c, 6.7466(1), 21.2565(7), 10.1462(2) Å, 90, 106.368(2), 90°, with Z = 4. The final disagreement factors were 0.069 and 0.061, for 721 [2σ(I)] and 1950 [2σ(I)] observed reflexions, respectively. Compound 1 presents the adamantyl residue disordered between the two usual conformations. The experimental dipole moments and the carbon-13 chemical shifts (both in hexadeuteriodi-methylsulfoxide and in the solid state) were measured and discussed in connection with the structure of these compounds.  相似文献   

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