2- OxO-l, 2H-PYRANE

Hetero-Diels-Alder reactions of l-oxa-l,3-butadienes with vinyl ethers, which lead to 3,4-dihydro-2H-pyran derivatives, are synthetically equivalent to Michael type conjugate additions. Wada and coworkers presented the first examples of a catalytic asymmetric intermolecular hetero-Diels-Alder reaction by the use of ( )-2-oxo-l-phenylsulfonyl-3-alkenes 25 and vinyl ethers 26 (Table 3) [25]. [Pg.1177]

A soln. of diethyl 2-amino-l-cyanoglutaconate (prepn. s. 677), salicyl aldehyde, and piperidine in ethanol warmed 0.5 hr. at 60 -> ethyl / -amino-ot-cyano-3-(2-oxo-l-benzopyran)acrylate (Y 91%) stirred and heated 2-3 min. at 100 with 2 N NaOH until an almost clear soln. results 2-cyanomethylene-2H-l-benzo-pyran-3-carboxylic acid (Y 93%). F. e. s. H. Junek and W. Wilfinger, M. 101, 1208 (1970). [Pg.364]

Lovastatin and mevastatin Lovastatin, (lS,3R,7S,8S,8aR)-l,2,3,7,8,8a-hexahydro-3, 7-dimethyl-8-[-[2R,4R]-[tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl]ethyl]-l-naphthyl (S)-2-methylbutyrate (20.2.7) is isolated from Monascus rubber [17] mA Aspergillus terreus [18], as is mevastatin (lS,3R,7S,8S,8aR)-l,2,3,7,8, 8a-hexahydro-7-metliyl-8-[-(2R,4R)-[tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl]ethyl]-l-naphthyl (S)-2-metliylbutyrate (20.2.8), which is isolated from Penicillium citrinum [19, 20] as well as from Penicillium brevicom-pactum [21]. [Pg.274]

Nl - BUTANOIC ACID, 2-METHYL-, 1,2,3,7,8,8a-HEXAHYDR0-3,7-DIMETHYL-8-(2-(TETRAHYDRO-4-HYDROXY-6-OXO-2H-PYRAN-2-YUETHYU-1-NAPHTHALENYL ESTER, (lS-(l-alph -(R ),3- lph 7-bete, 8-beta-(2S, 4S >,8a-beten-... [Pg.77]

R-(R, R )]-2-(4-fluorophenyl)- 3, 8-dihydroxy-5-(l-methylethyl)-3-phenyl-4-[(phe nylamino)-carbonyl]-lH-pyrrole-l-heptanoic acid or (2R-trans)-5-(4-fluorophenyl)-2-( 1 -methylethyl)-(V,4-diphenyl-l -[2-(tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl]-lH-pyrrole-3-carboxamide or pharmaceutically acceptable salts thereof. [Pg.52]

Chemical Name Butanoic acid, 2-methyl-, (lS,3R,7S,8S,8aR)-l,2,3,7,8,8a-hexahydro-3,7-dimethyl-8-(2-((2R,4R)-tetrahydro-4-hydroxy-6-oxo-2H-pyran-2-yl)ethyl)-l-naphthalenyl ester, (2S)-... [Pg.2089]

Phthalazine l,4-Dihydroxy-5,6,7,8-tetrahydro- E9a, 574 (3,4,5,6-H4—phthalanhydrid + N2H4) 2H-Pyran 2-( 3-Diazo-2-oxo-propy 1)-... [Pg.491]

Propansaure 2,2-Dimethyl-3-oxo-3-phenyl- -ethylester VII/2a, 572 (-COC1 -> -CO-R), 600 (Reformatsky-Reakt.) XIII/2a, 829f. (Reformatsky-Reakt.) 2H-Pyran 2-Benzyloxy-5-hydroxy-6-methyl-5,6-dihydro- VI/la,l,... [Pg.1157]

H-Pyran 6-(l-tert.-Butyloxycarbo-nyl-amino-ethyl)-4-methoxy-2-oxo-5,6-dihydro- E21c, 2933 [RHN-CHR-CHO + 1,3-(OR)2 — 1 -OSiR3 — 1,3-dien]... [Pg.1185]

DIMETHYL-4-OXO-2H-PYRAN-6-CARBOXYLIC ACID n-BUTYLMESITYLOXID OXALATE 2-CARBO-n-BUTOXY-6,6-DIMETHYL-5,6-DIHYDRO-l,4-PYRONE 3,4-DIHYDRO-2,2-DIMETHYL-4-OXO-2H-PYRAN-6-CARBOXYLIC ACID-n-BUTYL ESTER DIHDYROPYR-ONE 0,a-DIMETHYUa -CARBOBUTOXY-DIHYDRO-7-PYRONE 2,2-DIMETHYL-6-CARBOBUTOXY-2,3-DIHYDRO-4-PYRONE ENT 9 INDALONE... [Pg.240]

SYNS DEHYDROACETIC ACID, SODIUM SAI.T DHA-SODIUM HARVEN 4-HEXENOIC ACID, 2-ACETYL-5-HYDROXY-3-OXO, A-LACTONE, SODIUM derivative 3-(l-HYDROXYETHYLIDENE)-6-METHYL-2H-PYRAN-2,4(3H)-DIONE, SODIUM SALT SODIUM DEHYDROACETATE (FCC)... [Pg.1250]

Sauerstoff- oder schwcfcl-haltige sechsgliedrige Eeteroaromaten konnen untcr dem EinfluB von Licht aufgcspalten werden2-7. So entsteht z. B. aus 2,2,4,6-Tetraphenyl-2H-pyran oder -2H-thiopyran 5-Oxo-l,l,3,5-tetraphenyl-pentadien-(l,3) bzw. das entsprechende o-Thiono-1,1,3,5-tetraphenyl-pentadien-(l,3) ... [Pg.612]

Elenolide. 4-(l-Formyt-l-propenyl)-3,4-dihydro-2-oxo-2H-pyran- -carboxylic acid methyl ester. [Pg.554]

S-[2a-( ),3p,4p,5a[2i , 3i2 (li , 27 )]]]-9-[[3-methyl-l-oxo-4-trahydro-3,4-dihydroxy-5-[[3-(2-hydroxy-l-methylpropyl)oxiranyl]methyl]-2H-pyran-2-yl]-2-butenyl]o3Qr]nonanoic acid methylphenidan methylphenidate methyl phenidylacetate methyl a-phenyl-a-(2-piperidyl)acetate ( )-JV-methyl-3-phenyl-3-[(a,a,a-trifluoro-p-tolyDoxyJpropylamine... [Pg.1553]

Ethyl ethoxymethylenecyanoacetate (EMCE) followed by a-tetralone added drop-wise to a soln. of Na-ethoxide in dimethoxyethane, and stirred at room temp, overnight ethyl 5,6-dihydro-2-oxo-2H-naphtho[l,2-b]pyran-3-carboxylatc (Y 83%) allowed to react 14 hrs. with ethylene at 200° and... [Pg.518]

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