Reactions of 4-Hydroxy-5-methyl(phenyl)-2-styryl-6H-1,3-oxazin-6-ones with Nucleophiles

4-Hydroxy-5-methyl(phenyl)-2-styryl-6H-1,3-oxazin-6-ones react with hydrazine and phenylhydrazine to give the corresponding 3,5-substituted triazoles. Treatment of the title compounds with ethanol and methanol leads to formation of N-cinnamoylmalonamates. The structure of the products was confirmed by the IR and ¹H and ¹³C NMR spectra.     

Facile syntheses of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones and the corresponding 6-substituted 4-hydroxy-2-pyrones

A variety of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones 5a-l and the corresponding 6-substituted 4-hydroxy-2-pyrones 3a-l were prepared in high yields under mild reaction conditions by the reaction of 2,2,6-trimethyl-1,3-dioxin-4-one 4 with 1-acylbenzotriazoles 9 in the presence of LDA followed by thermal cyclization of 5a-l to 3a-l. Synthesis of novel 6-(1-benzoylalkyl)-2,2-dimethyl-1,3-dioxin-4-ones 12a-c was achieved by alkylation of dioxinone 5a and their subsequent cyclization gave 5-alkyl-4-hydroxy-2-pyrones 13a-c.     

Synthesis of 5-Alkyl(aryl)-2-alkylsulfanyl(alkoxy)-4-hydroxy-6H-1,3-oxazin-6-ones

Alkyl carbamates and S-alkyl thiocarbamates react with substituted malonyl dichlorides in boiling benzene to give the corresponding 2,5-substituted 4-hydroxy-6H-1,3-oxazin-6-ones. The reaction of S-methyl thiocarbamate with unsubstituted malonyl dichloride in boiling diethyl ether or benzene leads to formation of S-methyl (3-methylsulfanylaminocarbonyl-3-oxopropionyl)thiocarbamate and is not accompanied by cyclization, whereas in boiling toluene 4-hydroxy-2-methylsulfanyl-6H-1,3-oxazin-6-one is obtained.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 3, 2005, pp. 468–472.Original Russian Text Copyright © 2005 by Lalaev, Yakovlev, Zakhs.     

4H-3,1-Benzoxazin-4-ones methoxy-substituted 2-(2-arenesulfonylaminophenyl)-4H-3,1-benzoxazin-4-ones

Methoxy-substituted 2-(2-tosylaminophenyl)-4H-3,1-benzoxazin-4-one and 2-phenyl-4H-3,1-benzoxazin-4-one were synthesized. Their UV, IR, and luminescence spectra were studied. The position of the methoxy group affects the strength of the intramolecular hydrogen bond (IHB). The luminescence properties of methoxy-substituted 2-(2-tosylaminophenyl)-4H-3,1-benzoxazin-4-ones are associated with the strength of the IHB. The luminescence maximum is shifted to the short-wave region with strengthening of the IHB, and the luminescence intensity increase simultaneously.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1028–1032, August, 1971.The authors thank Yu. S. Ryabokobylko and A. O. Zisman for measuring the absorption spectra in the IR and UV regions.     

6-Aryl-2,2-dimethyl-1,3-dioxin-4-ones: Synthesis and Chemical Characteristics. (Review)

Methods for the production of 6-aryl-2,2-dimethyl-1,3-dioxin-4-ones and their thermolysis in the presence of nucleophiles and dienophiles are discussed     

Asymmetric reduction of 2,2-dimethyl-6-(2-oxoalkyl/oxoaryl)-1,3-dioxin-4-ones and application to the synthesis of (+)-yashabushitriol

The asymmetric transfer hydrogenation of a series of 2,2-dimethyl-6-(2-oxoalkyl)-1,3-dioxin-4-ones and 2,2-dimethyl-6-(2-oxoaryl)-1,3-dioxin-4-ones was achieved in high enantiomeric excess using a Ru(II) catalyst. The aryl substrates were most compatible with the methodology and this process facilitated a total synthesis of enantiomerically pure (+)-yashabushitriol.     

Generation and Reactions of Lithiated tert-Butyl and 2,6-Di(tert-butyl)-4-methylphenyl Cyclopropanecarboxylates

tert-Butyl and 2,6-di(tert-butyl)-4-methylphenyl (BHT) cyclopropanecarboxylates ( 4 , 6 , 24 , 25 ) are lithiated with LiN(i-Pr)₂ and t-BuLi, respectively. Reactions with alkyl halides, aldehydes, acyl chlorides, and heteroelectrophiles give α-substituted BHT esters which can be cleaved (t-BuOK/H₂O/THF) to the corresponding carboxylic acids or reduced (LiAlH₄/THF) to the cyclopropanemethanols.     

Reactions of (4E)-3-Arylamino-4-(hydroxyimino)naphthalen-1(4H)-ones and (4E)-2-[Arylamino(alkylamino)]-4-(hydroxyimino)naphthalen-1(4H)-ones with 2,2-Dihydroxyindane-1,3-dione

Russian Journal of Organic Chemistry - The reactions of 3-arylamino-1,4-naphthoquinone-4-oximes with 2,2-dihydroxyindane-1,3-dione proceed without involving the oxime group and lead to...     

Catalytic Hydrogenation of Chiral 2-(2-Furyl)-3,4-dimethyl-5-phenyloxazolidine

Reduction of chiral 2-(2-furyl)-3,4-dimethyl-5-phenyloxazo-lidines-1,3 by H₂/Raney nickel proceeds simultaneously as hydrogenation of the furan ring and opening of the oxazolidine ring on C2-O bond. Diastere-oselectivity in the first reaction was established as ca 40% and 80% depending on the configuration of the oxazolidine 1 and 2.     

The Reactions of 6-(tert-Butyl)-3-hydrazino-1,2,4-triazin-5(2H)-one with Carbonyl Compounds

The reaction of 6-(tert-butyl)-3-hydrazino-1,2,4-triazin-5(2H)-one with acetone and benzaldehyde yields the corresponding hydrazones. In the presence of thionyl chloride the benzaldehyde hydrazone is converted to 3-(tert-butyl)-6-phenyl-1,2,4-triazolo[4,3-b]-1,2,4-triazin-2(1H)-one and this can also be formed via the acylation of the starting hydrazinotriazinone using benzoyl chloride.     

A Facile Route to Quinazolin-4(3H)-ones Functionalised at the 2-Position

Treatment of 2-methoxyacetamidobenzonitriles or 2-chloroacetamidobenzonitrile with UHP and K₂CO₃ provides a convenient route to 2-methoxymethyl-or 2-chloromethylquinazolin-4(3H)-ones. In addition, demethylation of 2-methoxymethylquinazolin-4(3H)-ones with 48% HBr gives 2-hydroxymethylquinazolin-4(3H)-ones.     

Halogen-substituted 2-(2′-arenesulfonylaminophenyl)-4h-1,3-benzoxaz-4-ones

Chloro- and bromo-substituted 2-(2-tosylaminophenyl)-4H-1,3-benzoxaz-4-ones and 2-(2-tosylaminophenyl)-4H-naphtho[2,3-d]-1,3-oxaz-4-ones, their absorption spectra at room temperature, and their luminescence spectra at 77 deg K are described.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 12, pp. 1597–1601, December, 1970.     

2-(2’,6’-二氯苯基)-1,3-噻唑烷-4-酮衍生物的微波促进合成及抗真菌、 抗肿瘤活性研究

利用微波促进的方法, 以2,6-二氯苯甲醛、胺和巯基乙酸为原料, 合成了系列N-3位不同取代基团的噻唑烷酮衍生物. 部分化合物在Lawesson试剂作用下, 合成了其系列噻唑烷4-硫酮衍生物. 所有化合物通过IR, 1H NMR, MS和元素分析等方法确定结构. 测试了化合物对黄瓜白粉病菌的抑制活性和对宫颈癌细胞的毒性作用, 部分化合物表现出较好的生物活性.