Showing papers on "Benzopyran published in 1980"
TL;DR: In this article, the authors showed that the marked influence of an electron withdrawing 3-substituent in 5 is demonstrated by the fluorescence spectra of 7a,b (synthesized from 2d,e and ethyl 3-oxobutyrate), whose maxima are sharply shifted to the blue as compared with compounds 21-r.
54 citations
27 citations
21 citations
19 citations
18 citations
TL;DR: In this paper, a cyclization of γ-(2-thienyl)butryic acid with acid anhydrides gives 2-acyl derivatives as well as the expected 6,7-dihydrobenzo[b]thiophen-4(5H)one.
16 citations
TL;DR: In this article, the title compound, an isostere of 4,5′,8-trimethylpsoralen, was prepared in good yield from 7-[(2bromo-allyl)thio]-4,8dimethylcoumarin via a thio-Claisen rearrangement.
12 citations
Patent•
21 Nov 1980
TL;DR: Spiro hydantoins of formula (I), their optical isomers, and their salts with mineral or organic bases, are new as mentioned in this paper, and they are therefore useful in treating abnormal concns.
Abstract: Spiro hydantoins of formula (I), their optical isomers, and their salts with mineral or organic bases, are new. R3 is H, lower alkyl, alkenyl, alkynyl, hydroxyalkyl, alkoxyalkyl, or acyloxyalkyl, or aralkyl; R1 and R2 are the same or different and are H, lower alkyl, CF3, or a spiroalkylene (II). X is -CH2-, -O-, -S-, or -NR3-; n and n1 are 1 to 3; A is the residue of a benzene ring which may be substd. by 1-3 of halogens, lower alkoxy, CF3, CF30, CF3S, sulphamoyl, methylamino, sulphonyl, or dimethylamino sulphonyl; Z is O,S, or NR3; the dotted line is an opt. double bond; with the proviso that R1 and R2 are not both H when Z is O or S. Aldose-reductase inhibitors, they are therefore useful in treating abnormal concns. of galacticol and sorbitol in galactosemic patients, such as modifications of capillary function, discorders of nervous conduction, and diabetic cataracts with loss of transparency of the crystalline lens.
10 citations
9 citations
TL;DR: In this paper, an elegant method for the preparation of 4-oxo-4H-1-benzopyran-3-carboxaldehydes was reported independently by Nohara et al.
9 citations
TL;DR: Cycloaddition of dichloroketene to N,N-disubstituted 3-aminomethylene-4-chromanones gave in good yield 4-amino-3,3-dichloro,3,4-dihydro-5H-pyrano[3,2-c][1]benzopyran-2-ones only in the case of aromatic Nsubstitution as mentioned in this paper.
Patent•
12 Sep 1980
TL;DR: In this article, known and novel compounds of formula (I) where R 4 is hydrogen or lower alkyl and R 5 is a substituent are described, as well as methods for producing the compounds and methods for administering the compounds to cure or prevent rhinoviral infections.
Abstract: Known and novel compounds of formula (I)
wherein R 4 is hydrogen or lower alkyl, R 3 is hydrogen or lower alkyl and R 5 is a substituent, or R 3 and R 5 together form a group -CH 2 - or -CH 2 -CH 2 -, and R 1 and R 2 each represent four substituents or one or both R 1 and R 2 represents a methylenedioxy group and two substituents are active against viruses, especially rhinoviruses. Methods for producing the compounds are described, as are pharmaceutical formulations and methods for administering the compounds to cure or prevent rhinoviral infections.
TL;DR: The authors showed that diphenyl-nitrite imine gives the pyrazolobenzopyranone (3), benzonitrile oxide and N-benzylideneaniline N-oxide yield derivatives (6) and (7) of 2,3-bbenzoxazepin-1-one, and p-nitrophenyl azide forms a mixture of 2-p-nitro-3-(N-pyrrolidinecarbonyl)phthalimidine (10) and N-(p-n-
Abstract: 3-Pyrrolidino-2-benzopyran-1-one behaves differently towards various 1,3-dipoles : diphenyl-nitrite imine gives the pyrazolobenzopyranone (3), benzonitrile oxide and N-benzylideneaniline N-oxide yield derivatives (6) and (7), respectively, of 2,3-benzoxazepin-1-one, and p-nitrophenyl azide forms a mixture of 2-p-nitrophenyl-3-(N-pyrrolidinecarbonyl)phthalimidine (10) and N-(p-nitrophenylcarbamoyl)pyrrolidine (13).
TL;DR: In this paper, the synthesis of the title compound, a possible reactive intermediate responsible for the biological activity of precocene 1, is described, and the synthesis is described in detail.
Abstract: The synthesis of the title compound, a possible reactive intermediate responsible for the biological activity of precocene 1, is described.
TL;DR: In this article, the authors add 9,10-phenanthrenequinone or 3,5-di-tert-butyl-o-benzoquinone to N,N-dialkyl-3-alken-1-ynyl-1amines R2-CHCH-C≡C-NR12 (4) gives quinoid α-ALKENyl-γ-oxo-α,β-unsaturated carboxamides 6 or 8, respectively; these undergo a spontaneous ring-closure, or can be cycl
Abstract: Addition of 9,10-phenanthrenequinone or 3,5-di-tert-butyl-o-benzoquinone to N,N-dialkyl-3-alken-1-ynyl-1-amines R2-CHCH-C≡C-NR12 (4) gives quinoid α-alkenyl-γ-oxo-α,β-unsaturated carboxamides 6 or 8, respectively; these undergo a spontaneous ring-closure, or can be cyclised photochemically into 2H-phenanthro[9,10-b]pyran-4-carboxamides 7 or 2H-1-benzopyran-4-carboxamides 9.
Patent•
27 Mar 1980
TL;DR: Tetrazolyl-chromones of formula (where R is 1-3C alkoxy), are new anti-allergic agents as mentioned in this paper and may be used in the management of conditions such as hay fever and asthma, generally at dosages of 0.012-0.100 kg/kg.
Abstract: Tetrazolyl-chromones of formula (where R is 1-3C alkoxy), are new. (I) are anti-allergic agents. (I) may be used in the management of conditions such as hay fever and asthma, generally at dosages of 0.012-0.100 kg./kg. orally or by aerosol admin.. In an example, 8-methoxycarbonitrile is refluxed with NaN3 in THF containing AlCl3 to give 8-methoxy-3-(1H-tetrazol-5-yl)-4H-1-benzopyran-4-one.