1-Ethyl-2-methyl-5-hydroxy

The methods for preparing methyl mercaptan and /3-hydroxy-ethyl methyl sulfide are essentially those of Arndt and Kirner, respectively. 

The stereochemistry of the product resulting from the reaction of a 17-keto steroid with ethylidenetriphenylphosphorane is different from that of the 17-ethylidene steroids obtained by dehydration of 17a-ethyl-17/ -hydroxy compounds, Wolff-Kishner reduction of A -20-keto steroids or by sodium-alcohol or sodium-ammonia " reductions of 17-ethynyl carbinols. These latter products have generally been assumed to possess the trans configuration (C-21 methyl away from the bulk of the ring system) because of anticipated greater stability. The cis configuration for... 

The mercaptals obtained by the acid catalyzed reaction of J3-ketoesters, e.g., ethyl acetoacetate, with methyl thioglycolate (73) undergo the Dieckmann cyclization with alcoholic potassium hydroxide at lower temperatures to give ethyl 3-hydroxy-5-methyl-2-thiophenecarboxylate (74) in 75% yield. ° Besides ethyl acetoacetate, ethyl a-ethylacetoacetate, ethyl benzoyl acetate, and ethyl cyclopentanonecarboxylate were also used in this reaction/ It is claimed that /8-diketones, hydroxy- or alkoxy-methyleneketones, or /8-ketoaldehyde acetals also can be used in this reaction. From acetylacetone and thioglycolic acid, 3,5-dimethyl-2-thiophenecarboxyl-ic acid is obtained. ... 

Ethyl 7-hydroxy-3-methyl-5-oxo-2,3-dihydro-5//-pyrido[l, 2,3- /e]-1, 4-benzoxazine-6-carboxylate was obtained by cyclocondensation of 3-methyl-3,4-dihydro-2//-l,4-benzoxazine and triethyl methanetricarboxylate (00MI3). 

The 5-methyl-5-ethyloxazolidine-2,4-dione may be prepared by reacting methyl ethyl ketone with sodium cyanide and with ammonium thiocyanate followed by desulfurization. This intermediate may also be prepared by condensing a-hydroxy-a-methylbutyramide with ethyl chlorocarbonate or by condensing ethyl a-hydroxy-a-methylbutyrate with urea. Another method described (Traube and Aschar, Ber., 46, 2077-1913) consists in the condensation of ethyl a-hydroxy-a-methylbutyrate with guanidine followed by hydrolysis. 

To a cooled solution of 23 parts of sodium in 400 parts of dry ethanol are added 60 parts of dry urea and 132 parts of ethyl o-hydroxy-isobutyrate. The mixture is heated on a steam bath under reflux for about 16 hours and the liberated ammonia is removed from the solution by drawing a current of dry air through it at the boiling point. The solution of the sodium salt of 5,5-dimethyloxazolidine-2,4-dione so obtained is cooled and treated with 284 parts of methyl iodide. The mixture is allowed to stand at room temperature for 3 days, excess methyl iodide and ethanol are then removed by distillation under reduced pressure. 

Kaaret, T. W., and Bruice, T. C. (1990). Electrochemical luminescence with N(5)-ethyl-4a-hydroxy-3-methyl-4a,5-dihydrolumiflavin. The mechanism of bacterial luciferase. Photochem. Photobiol. 51 629-633. 

The same substrate (25) aud ethyl 2-chloroacetoacetate gave an analogous product, ethyl 3-hydroxy-3-methyl-3,4-dihydro-2//-1,4-thiazino[2,3-h]qui-noxahne-2-carboxylate (27) (KOH, EtOH, 20°C, 3 h 58%), which underwent dehydration to ethyl 3-methyl-2H-1,4-thiazino[2,3-h]quinoxaline-2-carboxy-late (28) (HCl gas, EtOH, 20°C, 15 h 60% analogs likewise). ... 

CN butanedioic acid 2-(dimethylamino)ethyl [5-hydroxy-4-(hydroxymethyl)-6-methyl-3-pyridinyl]methyl ester... 

Perfect stereochemical control in the synthesis of sy -a-methyl-/ -hydroxy thioesters has been achieved by asymmetric aldol reaction between the silyl enol ether of. S -ethyl propanethioate (1-trimethylsiloxy-l-ethylthiopropene) and aldehydes using a stoichiometric amount of chiral diamine-coordinated tin(II)... 

Isoxazole, 4-chloromethyl-3-ethyl-5-methyl-, 53, 71 Isoxazole, 3-ethyl-4-hydroxy-methy1-5-methyl-, 53, 70... 

Photolytic. Mathew and Khan (1996) studied the photolysis of metolachlor in water in the presence of kaolinite, montmorillonite, and goethite and fulvic acid under neutral and acidic conditions at 22 °C. Metolachlor degraded in all the treatments at both pH conditions. The rate of photolysis and degradation products formed was dependent on the duration of UV exposure, the initial pH of the solution, and the composition of the suspended/dissolved material. The following photoproducts identified included 2-hydroxy-A-(2-ethyl-6-methylphenyl)-A-(2-methoxy-l-meth-ylethyl)acetamide, 4-(2-ethyl-6-methylphenyl)-5-methyl-3-morpholine (major product forming at 74-84% yield), 8-ethyl-3-hydroxy-A-(2-methoxy-l-methylethyl)-2-oxo-l,2,3,4-tetrahydroquino-line, 2-chloro-A -(2-(l-hydroxyethyl)-6-methylphenyl)-7V-(2-hydroxy-l-methylethyl)acetamide, and 2-chloro-A -(2-ethyl-6-hydroxymethylphenyl)-A-(2-methoxy-l-methylethyl)acetamide. 

Acetyluracil — Ethyl 2-hydroxy-4-methyl-5-pyrimidinecarboxylate (XXXVI), which is prepared by the cyclization of the ureidomethylene derivative of aceto-acetic ester, can be caused to rearrange into 5-acetyluracil (XXXVII) in dilute alkali [304]. Compound (XXXVII) can also be prepared from diketene and ethyl carbamate, followed by treatment with ethyl orthoformate and cyclization with ammonia [305]. 

Ethyl-3-hydroxy-2-methyl-3,2-borazaropyridine (31), one of the very few non-fused (monocyclic) diheteraborines ever reported, was obtained by Gronowitz via desulfurization of 4-hydroxy-5-methyl-4,5-borazarothieno[2,3-c]pyridine (30) <68ACS1373>. Constitutional isomers 32 and 33 were obtained in a similar fashion <71ACS2435>. The X-ray crystal structure of the precursor to 33, namely, 7-hydroxy-6-methyl-7,6-borazarothieno[3,2-c]pyridine (34), was determined <74ACS(B)989>. 

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