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1.
The reaction of 1-methyl-3-(methylsulfinyl)-4(1 H)quinolinone ( 1 ) with acetic anhydride and thionyl chloride gave 3-[[(acetyloxy)methyl]thio]]-1-methyl-4(1 H)quinolinone ( 2 ) and 3-[(chloromethyl)thio]-1-methyl-4(1 H)quinolinone ( 3 ) respectively. 3-(Methylsulfinyl)-4(1 H)cinnolinone ( 4 ) gave the corresponding products when treated under similar conditions. Treatment of 8-methoxy-3-(methylsulfinyl)-4 H-1-benzopyran-4-one ( 11 ) with acetic anhydride and thionyl chloride gave bis addition vinyl Pummerer products 2,3-bis(acetyloxy)-2,3-dihydro-8-methoxy-3-(methylthio)-4 H-1-benzopyran-4-one ( 12 ) and 2,3-dichloro-2,3-dihydro-8-methoxy-3-(methylthio)-4 H-1-benzopyran-4-one ( 13 ), respectively. 相似文献
2.
The lipase-catalysed kinetic resolution of methyl esters of (±)-5-chloro-2,3-dihydro-1-benzofuran-2-carboxylic acid, (±)-6-chloro-2,3-dihydro-4 H-1-benzopyran-2-carboxylic acid, and (±)-6-chloro-2,3-dihydro-4 H-1-benzopyran-3-carboxylic acid, rigid analogues of clofibrate, was effected with fair to moderate enantioselectivities ( E=1.0–4.8), enantiomeric excesses of up to 86% and workable reaction rates. Enantiomerically pure ( R)- and ( S)-5-chloro-2,3-dihydro-1-benzofuran-2-carboxylic acids were obtained by fractional crystallisation of the diastereomeric salts of the corresponding racemic acid with (+)- and (−)-amphetamine from ethanol; the absolute configuration of the products were established by chemical correlation. 相似文献
3.
Investigation of the tubers of Eranthis hyemalis ( Ranunculaceae) afforded six chromenone glycosides. Their structures have been elucidated mainly by spectroscopic (FAB-MS, 2D-NMR techniques) and chemical methods (acidic and enzymatic hydrolysis) as 9-{[(β-D -glucopyranosyl)oxy]methyl}-8,11-dihydro-5-hydroxy-2-methyl-4 H-pyrano[2,3- g][1]benzoxepin-4-one ( 1 ), 9-{[(β-D -gentiobiosyl)oxy]methyl}-8,11-dihydro-5-hydroxy-2-methyl-4 H-pyrano[2,3- g][1]benzoxepin-4-one( 2 ), 9-{[(β-D -glucopyranosvl)oxy]melhyl}-8,11-dihydro-5-hydroxy-2-(hydroxy-methyl)-4 H-pyrano[2,3- g][1]benzoxepin-4-one( 3 ), 8-{(2 E)-4-[(β-D -glucopyranosyl)oxy]-3-methylbut-2-enyl}-5,7-dihydroxy-2-methyl-4 H-1-benzopyran-4-one ( 4 ), 8-{(2 E)-4-[(β-D -glucopyranosyi)oxy]-3-methylbut-2-enyl}-5,7-dihydroxy-2-(hydroxymethyl)-4 H-1-benzopyran-4-one ( 5 ), and 7-{[(β-D -glucopyranosy1)oxy]methyl}-2,3-dihydro-2-(l-hydroxy-1-methylethyl)-4-methoxy-5 H-furo[3,2- g][1]benzopyran-5-one ( 6 ). Compound 2 exhibited negative inotropic activity. 相似文献
4.
The condensation of 2,3-dihydro-6-methoxy-4 H-benzopyran-4-one ( 1 ) and 6-nitroveratr-aldehyde ( 2 ) gave the expected 2,3-dihydro-6-methoxy-3-(6-nitroveratrylidene)-4H-benzopyran-4-one ( 3 ) plus an unexpected product identified as 2,3-dihydro-3-(α-ethoxy-4,5-dimethoxy-2-nitrobenzyl)-6-methoxy-4H-benzopyran-4-one ( 4 ). 相似文献
5.
Summary The Claisen rearrangement of 7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one ( 2 a) gave 7-hydroxy-8-(1-phenyl-2-propenyl)-3-phenyl-(4 H)-1-benzopyran-4-one ( 3 a) and 2,3-dihydro-2,6-diphenyl-3-methyl-(7 H)furo[2,3-h]-1-benzopyran-7-one ( 7 a). 2-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one ( 2 b) afforded 4 b and 7 b. 8-Methyl-7-(3-phenyl-2-propenyloxy)-3-phenyl-(4 H)-1-benzopyran-4-one ( 12) gave only the alkali soluble product 7-hydroxy-8-methyl-6-(1-phenyl-2-propenyl)-3-phenyl-(4 H)-1-benzopyran-4-one ( 13). 3 a, 4 b, and 13 were further cyclized in acidic medium to 9 a, 10 b, and 14 followed by dehydrogenation.This paper is dedicated to Dr. F. M. Dean, Department of Organic Chemistry, Robert Robinson Laboratories, University of Liverpool, Liverpool, U. K., on his retirement 相似文献
6.
Enantiospecific Synthesis of (+)-( R)-6-Ethyl-2,3-dihydro-2-methyl-4 H-pyran-4-one, Sex-pheromonal Component of the Male Swift Moth Hepialus hecta L . A new synthesis of (+)?( R)-6-ethyl-2,3-dihydro-2-methyl-4 H-pyran-4-one (( R)- 8 ), sex-pheromonal component of the male swift moth Hepialus hecta L., has been performed from (?)-( R)-1-(1,3-dithian-2-yl)propan-2-ol with an enantiomeric excess of ? 97%. 相似文献
7.
Tandem arylation-reduction of a series of acyl heterocycles using phenyl-, 4-methylphenyl-, and 4-methoxy-phenyllithium reagents followed by lithium-ammonia-ammonium chloride reduction afforded the corresponding benzyl heterocycles. The acyl heterocycles surveyed in this study contained furan, 2,3-dihydro-4 H-1-benzopyran, 4 H-1-benzopyran, thiophene, 4,5,6,7-tetrahydrobenzo[ b]thiophene, 2,3-dihydro-4 H-1-benzothiopyran, and pyridine nuclei. All acyl heterocycles yielded the corresponding benzyl heterocycles except 2,3-dihydro-4 H-1-benzothiopyran-4-one, which selectively cleaved during reduction to give the corresponding 2-(1-arylpropyl)benzenethiols. 相似文献
8.
A convenient synthesis and structural characterization of ( Z)- and ( E)- trans-2,3-dihydro-2-methyl-3-(1,2,4-triazolyl)-4 H-1-benzopyran-4-one oxime ethers has been achieved. By analysis of vicinal interproton coupling constants, it is believed that trans-2,3-dihydro-2-methyl-3-(1,2,4-triazolyl)-4 H-1-benzopyran-4-ones which exist predominantly in the diequatorial half-chair or sofa conformation was found to exist predominantly in the diaxial orientation upon conversion to the corresponding oxime ether derivatives. 相似文献
9.
Although the previously reported (1,2) chemical reduction of 2,3-dihydro-3-(6-nitroveratry-lidene)-4 H-benzopyran-4-one with stannous chloride occurred with cyclization to the 6 H-[1]-benzopyrano [4,3- b]quinoline ring system, the present study of the catalytic (palladium/carbon) reduction of 2,3-dihydro-6-methoxy-3-(6-nitroveratrylidene)-4 H-benzopyran-4-one ( 1 ) (3) has indicated that other products in addition to the expected benzopyranoquinoline ( 3 ) may be isolated, depending upon the conditions of the reduction. The products of the reduction of 1 , isolated and structurally determined, include 2,9,10-trimethoxy-6 H-[1]benzopyrano-[4,3- b]quinoline(3),2,9,10-trimethoxy-6a,7,12,12a-tetrahydro-6H-[1]benzopyrano[4,3- b]-quinoline (2), the N-oxide of 3 (6 ), and 6-hydroxy-2,9,10-trimethoxy-6 H-[l]benzopyrano-[4,3- b Jquinoline ( 8 ). 相似文献
10.
The reaction of anthranilonitrile with 2-chloroethyl isocyanate yields 2-[3-(2-chloroethyl)ureido]benzo-nitrile ( 6 ) which, upon heating, or treatment with base, undergoes a double cyclization to form 2,6-dihydroimidazo[1,2- c]quinazolin-5-(3 H) one ( 8 ) in excellent yield. When heated with hydrochloric acid, 6 is converted initially into 2-(2-chloroethylamino)-4 H-[3,1]benzoxazin-4-one ( 18 ) and further into 3-(2-chloroethyl)-2,4-(1 H,3 H)quinazolinedione ( 15 ). The acid-catalyzed reaction of 2,3-dihydro-5 H-oxazolo[2,3- b]quinazolin-5-one ( 14 ) with nucleophilic reagents yields 3-substituted 2,4-(1 H,3 H)quinazolinediones. 相似文献
11.
Mitsunobu displacement of (−)-(1 S,4 R,5 S,6 S)-4,5,6-tris{[( tert-butyl)dimethylsilyl]oxy}cyclohex-2-en-1-ol ((−)- 12 ; a (−)-conduritol-F derivative) with 4-ethyl-7-hydroxy-2 H-1-benzopyran-2-one ( 16 ) provided a 5a-carba- β-D -pyranoside (+)- 17 that was converted into (+)-4-ethyl-7-[(1′ R,4′ R,5′ S,6′ R)-4′,5′,6′-trihydroxycyclohex-2′-en-1′-yloxy]-2 H-1-benzopyran-2-one ((+)- 5 ) and (+)-4-ethyl-7-[(1′ R,2′ R,3′ S,4′ R)-2′,3′,4′-trihydroxycyclohexyloxy]-2 H-1-benzopyran-2-one ((+)- 6 ). The 5a-carba- β-D -xyloside (+)- 6 was an orally active antithrombotic agent in the rat (venous Wessler's test), but less active than racemic carba- β-xylosides (±)- 5 and (±)- 6 . The 5a-carba- β-L -xyloside (−)- 6 was derived from the enantiomer (+)- 12 and found to be at least 4 times as active as (+)- 6 . (+)-4-Cyanophenyl 5-thio- β-L -xylopyranoside ((+)- 3 ) was synthesized from L -xylose and found to maintain ca. 50% of the antithrombotic activity of its D -enantiomer. Compounds (±)- 5 , (±)- 6 , and (−)- 6 are in vitro substrates for galactosyltransferase 1. 相似文献
12.
The crystal structure of chromone hydrazonium salt (±)-1-hydroxy-1-oxo-3-phenyl-1,3-dihydro-1λ 5-2,1-oxaphospholo[4,5-b]-4 H-1-benzopyran-4-one ( 2) and its acid (±)-1-hydroxy-1-oxo-3-phenyl-1,3-dihydro-1λ 5-2,1-oxaphospholo[4,5-b]-4 H-1-benzopyran-4-one ( 3) have been solved. Condensed rings are almost planar, the P atom adopts nearly tetragonal geometry. The molecular packing is influenced by inter- and intramolecular contacts, which can be recognized as hydrogen bonds. 相似文献
13.
Isatoic anhydride ( 1a ) and 5-chloroisatoic anhydride ( 1b ) were treated with 2-(1-methylhydrazino)ethanol ( 2 ) to produce 2-aminobenzoic acid 2-(2-hydroxyethyl)-2-methylhydrazide ( 3a ) and its 5-chloro analog 3b , respectively. Treatment of 3a and 3b with carbon disulfide gave, respectively, 2,3-dihydro-3-[(2-hydroxyethyl)methylamino]-2-thioxo-4-(1 H)quinazolinone ( 4a ) and its 6-chloro analog 4b . Compounds 4a and 4b afforded 5,6-dihydro-5-methyl-2-thioxo-4 H,8 H-[1,3,5,6]oxathiadiazocino[4,5- b]quinazolin-8-one ( 5a ) and its 10-chloro analog 5b , respectively, upon treatment with thiophosgene. Compound 5a could be produced directly from 3a and thiophosgene. Treatment of 4a and 4b with trifluoroacetic anhydride followed by potassium carbonate gave 3,4-dihydro-4-methyl-2 H,6 H-[1,3,4]thiadiazino[2,3- b]quinazolin-6-one ( 7a ) and its 8-chloro analog 7b , respectively. Treatment of 4a with thionyl chloride also gave 7a , but 4b and thionyl chloride afforded a mixture of 7b and 8-chloro-3,4-dihydro-4-methyl-2 H,6 H-[1,3,4]oxadiazino[2,3- b]quinazolin-6-one ( 10 ). The dimethyl analogs of 4a and 4b ( 13a and 13b ) upon treatment with thiophosgene afforded 3,4-dihydro-2,2,4-trimethyl-2 H,6 H-[1,3,4]oxadiazino[2,3- b]quinazolin-6-one ( 14a ) and its 8-chloro analog 14b , respectively. 相似文献
14.
To search for novel antihypertensive heterocycles in the condensed quinazoline series, two representative compounds were synthesized via a suitable reaction sequences. Treating anthranilonitrile with allyl isocyanate gave 2-(allylureido)benzonitrile ( 10 ) in a quantitative yield. Compound 10 was cyclized to 3-allylquinazoline-2(1 H, 4(3 H)-dione ( 11 ). Bromination of 11 in carbon tetrachloride converted it into the corresponding 3-(2,3-dibromopropyl) derivative ( 12 ) in 92% yield. Ring closure of 12 was effected by the action of alkali to afford 2-bromomethyl-2,3-dihydro-5 H-oxazolo[2,3- b]quinazolin-5-one ( 13 ). The title compound, 2-(4-benzylpiperazin-1-ylmethyl)-2,3-dihydro-5 H-oxazolo[2,3- b]quinazolin-5-one ( 7 ) could be obtained by a reaction of either 12 or 13 with 1-benzylpiperazine respectively. Starting from the readily available 3-allyl-2 H-thioxoquinazolin-4(3 H)-one ( 16 ) via the analogous reactions gave the 2-bromomethyl-2,3-dihydro-5 H-thiazolo[2,3- b]-quinazolin-5-one ( 19 ) in good yield. However, the reaction of 19 with 1-benzylpiperazine provided another target compound, 2-(4-benzylpiperazin-1-ylmethyl)-2,3-dihydro-5 H-thiazolo[2,3- b]quinazolin-5-one ( 8 ) only in poor yield (8%). As major product, the dehydrobrominated compound, 2-methylene-2,3-dihydro-5 H-thiazolo[2,3- b]quinazolin-5-one ( 22 ) was isolated. A preliminary pharmacological evaluation revealed that both compounds 7 and 8 are devoid of the antihypertensive activity. 相似文献
15.
Hydrogenation of 4,7-dimethylcoumarin ( 1 ) in alkaline medium has been shown to furnish a mixture of (±)- trans-4aβ( H),8aα( H)-octahydro-4α,7β-dimethyl-2 H-1-benzopyran-2-one ( 2 ), (±)- trans-4aβ( H),8aα( H)-octahydro-4α,7α-dimethyl-2 H-1-benzopyran-2-one ( 3 ) and (±)- cis-4aα( H),8aα( H)-octahydro-4α,7α-dimethyl-2 H-1-benzopyran-2-one ( 4 ) in 40:25:35:ratio, respectively. The stereochemistry of the major hydrogenation product 2 , has been established by transforming it to p-menthane derivatives e.g. (±)-2 ( R)-[2′( R)hydroxy-4′( R) methylcyclohex-(1′ S)-yl]propan-1-ol ( 20 ) and (±)- trans-3α,6β-dimethyl-3aβ( H),7aα( H)-octahydrobenzofuran ( 12 ). Starting from a mixture of lactones 2, 3 and 4 , lactone 3 has been obtained in pure state employing a sequence of reactions. 相似文献
16.
rel-(2 R,3 R)- N-Benzoylamino-6,7-bis(methoxycarbonyl)-2,3-dihydro-1-oxo-1 H,5 H-pyrazolot[1,2- a]-pyrazoles 5 , accesible by cycloaddition of dimethyl acetylenedicarboxylate ( 3 ) to (1Z)- rel-(4 R,5 R)-1-aryl-methylidene-4-benzoylamino-5-phenyl-3-pyrazolidinone-1-azomethine imines 4 , undergo oxidative ring cleavage with methanolic bromine giving rel-(2 R,3 R)- N-benzoyl-3-phenyl-3-[5-aryl-3,4-bis(methoxy-carbonyl)pyrazolyl-1]alanine methyl esters 6 as products. 相似文献
17.
The urea 1 obtained from anthranilonitrile and 3-chloropropyl isocyanate is converted into 3-(3-chloropropyl)-2,4(1 H,3 H)quinazolinedione ( 4 ) when heated with hydrochloric acid, whereas it undergoes a double cyclization to form 2,3,4,7-tetrahydro-6 H-pyrimido[1,2- c]quinazolin-6-one ( 3 ) upon heating, or treatment with ammonia. On the other hand, the urea 5 formed from methyl anthranilate and 3-chloropropyl isocyanate cyclizes in three different ways, when treated with ammonia, potassium bicarbonate, or concentrated sulfuric acid, to yield compound 4 , 3,4-dihydro-2 H,6 H-[1,3]oxazino[2,3- b]quinazolin-6-one ( 9 ), or 2-[(3-chloropropyl)amino]-4 H-3,1-benzoxazin-4-one ( 6 ), respectively. Acid-catalyzed reactions of compound 9 with nucleophilic reagents proceed with opening of the oxazine ring and readily yield various 3-substituted 2,4(1 H,3 H)-quinazolinediones. 相似文献
18.
The reaction of 6-(R-amino)-5-acetyl-4-methylsulfonyl-2-phenylpyrimidines with amines was studied. 6-Arylamino derivatives react with alkylamines to form 6-alkylamino-4-arylamino-5-acetyl-2-phenylpyrimidines, which upon refluxing in benzene with dimethylformamide dimethylacetal are converted to 4-alkylamino-8-aryl-2-phenylpyrido[2,3-d]pyrimidin-5(8H)-ones. The cyclization proceeds selectively with participation of the arylamino group only, the alkylamino group being not involved. At the same time, refluxing of 5-acetyl-4,6-dibenzylamino-2-phenylpyrimidine with dimethylformamide dimethylacetal in toluene affords the product of condensation on the acetyl group, which upon refluxing in o-xylene transforms to 4-benzylamino-8-benzyl-2-phenylpyrido[2,3-d]pyrimidin-5(8H)-one. 相似文献
19.
The synthesis of 2-(1 H-imidazol-1-yl)-2,3-dihydro-2 H-1-benzopyran-4-ones (I) through 3-bromo-2,3-dihydro-4 H-1-benzopyran-4-ones or more conveniently through chroman ring closure from 2-(1 H-imidazol-1-yl)-2′-hydroxyacetophenones is described. The ring closure also works well for the pyrazolyl derivatives. Compounds I and the corresponding imidazolylchromanols, -chromenes, and -chromans derived from the former, were pharmacologically investigated. 相似文献
20.
New heterocyclic structures. [1,2,5]Thiadiazolo[3′,4′:4,5]pyrimido-[2,1-b][1,3]thiazine and thiazolo[3,2a][1,2,5]thiadiazolo[3,4-d]pyrimidine
Derivatives of two new molecular structures, namely, 7,8-dihydro-6 H,10 H-[1,2,5]thiadiazolo[3′,4′:4,5]pyrimido[2,1- b][1,3]thiazin-10-one and 6,7-dihydro-9 H-thiazolo[3,2- a][1,2,5]thiadiazolo[3,4- d][pyrimidin-9-one, and derivatives of N-substituted sulfamic acid, namely, (8-amino-3,4-dihydro-2 H,6 H-pyrimido[2,1- b][1,3]thiazin-6-on-7-yl)sulfamic acid and (7-amino-2,3-dihydro-5 H-thiazolo[3,2- a]pyrimidin-5-on-6-yl)sulfamic acid, were separated out as by-products in the reduction reaction of 8-amino-3,4-dihydro-7-nitroso-2 H,6 H-pyrimido[2,1- b][1,3]thiazin-6-one and 7-amino-2,3-dihydro-6-nitroso-5 H-thiazolo[3,2- a]pyrimidin-5-one derivatives, respectively, with sodium hydrosulfite. A mechanism of reaction, which hypothesizes the action of sodium hydrosulfite in an asymmetic form, is proposed. The results of single-crystal X-ray investigation on 7,8-dihydro-6 H,10 H-[1,2,5]thiadiazolo[3′,4′:4,5]pyrimido[2,1- b][1,3]thiazin-10-one (R = 0.032 for 863 reflections) and (8-amino-3,4-dihydro-2 H,6 H-pyrimido[2,1- b]- [1,3]thiazin-6-on-7-yl)sulfamic acid, sodium salt (R = 0.028 for 3507 reflections) are reported. 相似文献
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