Spiro -3 -ones, 4-hydroxy

Chemical Name ( )-[Hydroxy-6-methoxy-5-methyl-11 H-cyclopenta[i,j] -isoquinolinel -7-spiro-1 (2 -cyclohexadiene4-one)... 

A number of novel spiro heterocycles, including the triazepinethione 146 have been derived from 3-hydroxy-3-(2-oxocyclohexyl)indolin-2-one 145 by condensation with active methylene compounds <00SC1257>. A condensation process was also used to prepare tricyclic triazepinones related to the non-nucleoside reverse transcriptase inhibitor nevirapine <00JHC1539>. 

The parent compound and a set of monosubstituted bis(acylamino)diarylspiro-X4-sulfanes (360 X = H, Me, MeO, Cl, NO2) undergo hydrolysis to the corresponding sulfoxides (361). The probable mechanism involves rate-determining cleavage of one of the S—N hypervalent bonds in the spiro ring with simultaneous proton transfer to the nitrogen atom. The hydroxide ion which is formed thereby then attacks the sulfur atom in a fast step to form a diaryl(acylamino)hydroxy-k4-sulfane (362), which is converted into the sulfoxide (361) (Scheme 47). ... 

N-Methyl-4-hydroxy-2-quinolone 183 in a three-component reaction gives spiro pyrano[3,2-c]qionoline-2-ones (02MI2), but indolones 213 with 4-hydroxy-6-methyl-2-pyridone 177 react in a complicated way (97BCJ1625). Ethoxycarbonyl-methylene indolone (Z = COOEt) forms pyrans 224, while dicyano analogs (Z = CN) yield substituted quinoline 225 (Scheme 85). 

Another total synthesis of sufentanil has been described the cyclization of 2-(2-thienyl)ethylamine with allyl-trimethylsilane and formaldehyde gives 4-hydroxy-1-[2-(2-thienyl)ethyl]piperidine, which is oxidized with oxalyl chloride in DMSO/dichloromethane to 1-[2-(2-thienyl) ethyl]piperidin-4-one. The epoxidation of this compound by means of trimethylsulfonium iodide and the sodium salt of DMSO yields the spiro-epoxide, which is opened with... 

Chlorophenyl)glutarate monoethyl ester 87 was reduced to hydroxy acid and subsequently cyclized to afford lactone 88. This was further submitted to reduction with diisobutylaluminium hydride to provide lactol followed by Homer-Emmons reaction, which resulted in the formation of hydroxy ester product 89 in good yield. The alcohol was protected as silyl ether and the double bond in 89 was reduced with magnesium powder in methanol to provide methyl ester 90. The hydrolysis to the acid and condensation of the acid chloride with Evans s chiral auxiliary provided product 91, which was further converted to titanium enolate on reaction with TiCI. This was submitted to enolate-imine condensation in the presence of amine to afford 92. The silylation of the 92 with N, O-bis(trimethylsilyl) acetamide followed by treatment with tetrabutylammonium fluoride resulted in cyclization to form the azetidin-2-one ring and subsequently hydrolysis provided 93. This product was converted to bromide analog, which on treatment with LDA underwent intramolecular cyclization to afford the cholesterol absorption inhibitor spiro-(3-lactam (+)-SCH 54016 94. 

Whereas a triplet 1,4-biradical has been assigned as the most probable intermediate at that time, later work on intramolecular trapping reaction favored the assumption of radical ion pairs [46]. Efficient lactonization reaction to form 51 during irradiation of pent-4-enoic acid 50 and 48 accounts for an olefin radical cation which undergoes electrophilic addition towards the carboxyl group. Another type of rearrangement has been detected in the photoreaction of tetramethylallene and 48 [47]. 5-Hydroxy-indan-2-ones 52 are formed in high yields probably via instable spiro-oxetanes 49b as intermediates. 

The non-volatile pungent oil obtained by solvent extraction of the spice was named gingerol (Purseglove et al., 1981). Spiro and Kandiah (1989) studied the extraction kinetics of [6]-gingerol, l-(4 -hydroxy-3 -methoxyphenyl)-5-hydroxydecan-3-one (Kandiah and Spiro, 1990). 

Bromo-2-thioaryloxy-3-methylcyclohexen-l-one, 2a, is an achiral compound. Its conformation can be fixed in a chiral twisted form in the solid state, but it forms racemic crystals, and hence the solid-state reaction produces a racemic mixture of (—) and (+ )3a. A method for achieving an enantioselective reaction is to form an inclusion complex with a chiral host compound, (— )-(R,R)-( — )-fran.s-2,3-bis(hydroxy diphenyl methyl)-1,4-dioxa spiro-[4,4]nonane, ( — )-4. In a typical experiment, a benzene (5 mL) and hexane (5 mL) solution of (— )-4 and 2a left at room temperature for 24 h gave a 1 1 inclusion compound of (-)-2a and 4 as colorless crystals [38]. 

SODIUM SODIUM FLUORESCEIN SODIUM FLUORESCEINATE SODIUM SALT of HYDROXY-o-CARBOXY-PHENYL-FLUORONE SOLUBLE FLUORESCEIN SPIRO(ISOBENZOFURr N)-l(3H),9 -(9H)XANTHENE-3-ONE, 3, 6 -DIHYDROXY-DISODIUM SALT URANTN URANINE A EXTRA URANINE USP XII URANINE YELLOW 11824 YELLOW ... 

Aromatization.— The influence of substituents upon the aromatization of 1,4-dien-3-ones has been further investigated. The 6a-phenyldienone (429) rearranges in trifluoroacetic anhydride to give the normal l-hydroxy-4-methyl aromatic product (431), accompanied by lesser amounts of the 4-hydroxy-l-methyl isomer (432) and other products. Assuming a spiro-cation intermediate... 

Upon epoxidation with peracids, alkylidenecycloproparenes react at the exocyclic double bond and are converted to hydroxy ketones 15. Epoxidation of l-(diphenylmethylene)cyclo-propa[6]naphthalene with dimethyldioxirane at — 18 "C afforded the epoxide, 3, 3 -diphenyl-spiro l//-cyclopropa[2ft]naphthalene-l,2 -oxirane (16), which was characterized by H and CNMR. This is the first oxaspiropentene ever characterized. Under non-acidic conditions rearrangement of the epoxide 16 to 2,2-diphenylcyclobuta[6]naphthalen-l(2//)-one (17) occurred in 86% overall yield. 

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