3- Methyl-2-butanol derivatives

Di methylo I butanol or Bis(hydroxy methyl-butanol and Derivatives... 

Using indolyl-based substrate analogs such as 5-bromo-4-chloro-3-indolyl-ace-tate, butyrate, or propionate (X-acetate, X-butyrate, and X-propionate) for esterases and using the p-rosaniline assay coupled with ethanol, butanol, or propanol for alcohol dehydrogenases we were able to isolate several hundred candidates in the first level of a hierarchical screen. An intermediate screen was then used to characterize and compare the esterase candidates. We used nitrophenyl and methyl-umbelliferyl derivatives to analyze esterase candidates and their preference for chain length. 

FIGURE 12.2 Formation of the higher alcohols 3 -methyl-1 -butanol, isobutanol, 2-methyl-1 -butanol, and 1-butanol derived from intermediates of the branched-chain amino acid pathways. Adh, alcohol dehydrogenase KDC, 2-ketoacid decarboxylase. 

TABLE 12.3 Relevant Yields and Titers of Isobutanol, 2-Methyl-l-Butanol, 3-Methyl-l-Butanol, 1-Butanol Derived of the Metabolic Pathways of Branched-Chain Amino Acids... 

The preparation of this tetrapeptide described by Hutchings et al. (303) involves essentially the following operations. The culture medium, after removal of the bacteria, is adjusted to pH 3.0. The peptide is adsorbed on norit A, and after being washed with ethanol, is eluted with hot (70° C.) ammoniacal ethanol. The eluate is adjusted to pH 8.0, 8S % ethanol is added followed by a saturated solution of barium chloride, and the solution is cooled at 0° C. The barium pteroyltriglutamate precipitates, and its methyl ester derivative is prepared from the precipitate. The ester is extracted by butanol, and the butanol solution evaporated to dryness. The residue is redissolved by hot methanol, and the ester precipitates on cooling. The preceding purification is repeated, and finally, a controlled hydrolysis liberates the free acid which crystallizes. 

Oxidative rearrangement takes place in the oxidation of the 1-vinyl-l-cyclo-butanol 31, yielding the cyclopentenone derivative 32[84], Ring contraction to cyclopropyl methyl ketone (34) is observed by the oxidation of 1-methylcyclo-butene (33)[85], and ring expansion to cyclopentanone takes place by the reaction of the methylenecyclobutane 35. [86,87]... 

The relative basicity and acidity of isothiazole and its methyl derivatives have been compared by IR spectroscopy (77MI41702). The isothiazoles, dissolved in inert solvents (e.g. CCI4, CS2) containing traces of butanol (a proton donor), interact with the butanol OH... 

Solid esters are easily crystallisable materials. It is important to note that esters of alcohols must be recrystallised either from non-hydroxylic solvents (e.g. toluene) or from the alcohol from which the ester is derived. Thus methyl esters should be crystallised from methanol or methanol/toluene, but not from ethanol, n-butanol or other alcohols, in order to avoid alcohol exchange and contamination of the ester with a second ester. Useful solvents for crystallisation are the corresponding alcohols or aqueous alcohols, toluene, toluene/petroleum ether, and chloroform (ethanol-free)/toluene. Esters of carboxylic acid derived from phenols... 

There are very few homolytic reactions on triazolopyridines. A suggestion that the ring opening reactions of compound 1 involved free radical intermediates is not substantiated (98T9785). The involvement of radical intermediates in additions to ylides is discussed in Section IV.I. The reaction of radicals with compound 5 and its 1-substituted derivatives gives 4-substituted compounds such as 234 (96ZOK1085). A more detailed study of the reaction of the 1-methyl and 1-phenyl derivatives with r-butanol and ammonium persulfate produced 4-methyl substitution with a silver nitrate catalyst, and the side chain alcohol 235 without the catalyst (96ZOK1412). 

Hydroxypyridine (86, R = H) and its derivatives also belong to the class of heterocyclic enols. In benzene and dioxane, 3-hydroxy-pyridine occurs as the neutral molecule (and not as a betaine).Its reaction with diazomethane, in heterogeneous media, gives a mixture of 3-methoxypyridine (86, R = Me) (10%) and l-methyl-3-hydroxy-pyridinium betaine (87) (30%If tert-butanol is used as a... 

The phenylcarbamate derivative 23j also showed chiral recognition for many racemates in CDCI3 (Figure 3.38). Figure 3.39 shows the 1H NMR spectra of ( )-2-butanol in the absence and presence of 23j. In the case of secondary alcohols, such as 2-butanol, 2-heptanol, and 2-octanol, the methyl protons at the end of the longer chain and remote from the stereogenic center were enantiomerically separated in the presence of 23j, and the methine and... 

Fig. 4.3 Behavioral bioassay by using a felinine derivative. Felinine purified from cat urine by HPLC was dissolved in water at a concentration of lOmg/ml, and 200 pi of the solution was stored in a 1.5-ml eppendorf tube at room temperature for 5 days. GC-MS analysis detected 3-mercapto-3-methyl-l-butanol in the headspace gas of the tube. The cat (6-year-old castrated male) was able to sniff the opening of the tube, but not contact the felinine solution. The cat sniffed 3-mercapto-3-methyl-l-butanol with considerable interest (18s and 25s) and then licked his lips five times (37 s)...

Ethynylallenes [35], the didehydro analogs of vinylallenes, have also been known for some time, the parent system 7 having been obtained in 1960 by reduction of 3-chloro-l,4-pentadiyne (101) with zinc-copper couple in butanol [36] and the 5-methyl derivative 103 by base-catalyzed isomerization of 1,4-hexadiyne (102) with sodium ethoxide in ethanol (Scheme 5.13) [9]. 

In the above cited example [/ (a)] the rotation of the plane of polarization is to the right (clockwise), the lactic acid is dextrorotatory (Latin dexter = right) designated by d if the rotation is to the left (counterclockwise), the lactic acid [/ (h) is levorotatoiy (Latin laevus = left) designated by 7 . In the same vein, the example [ii (h) represents 1-2 methyl-1-butanol a product derived from fusel oil. 

The advantage of trimethylsilyl (TMS) derivatives lies in the simplicity of the derivatization procedure, which is carried out by the addition of N,0-bis(trimethylsilyl)trifluoroacetamide (BSTFA) in acetonitrile and heating for approximately 2 h at 150 °C under anhydrous conditions in a sealed tube. However, there may be problems owing to the formation of multiple derivatives of each amino acid. Another technique involves the formation of n-butyl esters of the amino acids and their subsequent trimethylsilylation by a similar procedure. The n-butyl esters are formed by heating the amino acids for 15 min in n-butanol and HC1 and these are then converted to the A-TMS-n-butyl ester derivatives. A-acyl amino acid alkyl esters are commonly used. Acetylation of the butyl, methyl or propyl esters of amino acids,... 

Alkyl alkanoates are reduced only at very negative potentials so that preparative scale experiments at mercury or lead cathodes are not successful. Phenyl alkanoates afford 30-36% yields of the alkan-l-ol under acid conditions [148]. Preparative scale reduction of methyl alkanoates is best achieved at a magnesium cathode in tetrahydrofuran containing tm-butanol as proton donor. The reaction is carried out in an undivided cell with a sacrificial magnesium anode and affords the alkan-l-ol in good yields [151]. In the absence of a proton donor and in the presence of chlorotrimethylsilane, acyloin derivatives 30 arc formed in a process related to the acyloin condensation of esters using sodium in xylene [152], Radical-anions formed initially can be trapped by intramolecular addition to an alkene function in substrates such as 31 to give aiicyclic products [151]. 

Change-transfer complexes of solute-alcohol stoichiometry 1 2 have been reported by Walker, Bednar, and Lumry3 for indole and certain methyl derivatives (M) in mixtures of associating solvents n-butanol and methanol (Q) with n-pentane these authors introduced the term exciplex to describe the emitter of the red-shifted structureless fluorescence band which increases in intensity with the alcohol content of the mixed solvent. The shift of the exciplex band to longer wavelengths as the solvent polarity is increased, described by Eq. (15), confirms the dipolar nature of the complex that must have the structure M+Q2. No emission corresponding to the 1 1 complex is observed in these systems which indicates (but does not prove) that the photo-association involves the alcohol dimer. The complex stoichiometry M+Q determined from (Eqs. 9, 10, and 12)... 

BA standards methyl esters are prepared by adding 100 pi of 3% anhydrous methanolic hydrochloric acid, to 5-20 pg of each BA and storing them at room temperature for 2 h, followed by solvent evaporation at 55°C under nitrogen. The -butyl esters are prepared by addition of 100 pi of -butanol to 5-20 pg of each BA, followed by addition of 20 pi of a 40% solution of hydrogen chloride in dioxane. The reaction mixtures are heated at 60°C for 4 h, followed by overnight incubation at room temperature, and then evaporated at 60°C under nitrogen. Sil-Prep [hexamethyldisilazane-trimethylchlorosilane-pyridine (3 1 9)] is used for the preparation of TMS ether derivatives of BA esters. The esterified BAs (5-10 pg) are reacted... 

Synthesis The reaction of benzothiazolo-3(2H)-one-1,1-dioxide with methyl chloroacetate gives the methyl 2(3H) acetate derivative, which is isomerized with sodium methoxide in toluene/terf-butanol yielding methyl 4-hydroxy-2H-1,2-benzothiazine-3-carboxylate-1,1 -dioxide. The subsequent methylation with methyl iodide in methanol yields the 2-methyl compound. Finally this compound is treated with 2-amino-5-methylthiazole in xylene (Trummlitz et al. (Thomae GmbH), 1979 Trummlitz et al., 1989 Kleemann et al., 1999). 

Cyclization of 1-isoquinolyl derivatives (201) in a cold solution of perchloric acid or in cone, sulfuric acid at room temperature afforded 4-hydroxy-3,4-dihydro-2//-[l,3]thiazino[2,3-a]isoquinolinium perchlorates (202) and 2H-[l,3]thiazino[2,3-a]isoquinolinium salts (203), respectively (74IJC1242). Heating l-[(3-phenyl-3-hydroxypropyl)thio]isoquinoline in PPA yielded the l-phenyl-3,4-dihydro-2//-[l,3]thiazino[2,3-a]isoquin-olinium salt (74IJC1242). 6,7-Dihydro derivatives of 2//-[l,3]thiazino-[2,3-a]isoquinolinium perchlorate (203, R = Me) and 4-methyl-2,3,4,6,7, llh-hexahydro-[l,3]thiazino[2,3-a]isoquinoline were obtained by cyclization of the 3,4-dihydro derivative of 201 (R = Me) and 4-[(l,2,3,4-tetrahydroisoquinolin-l-yl)thio]-2-butanol, respectively, in cone, sulfuric acid or in PPA [81IJC(B)372],... 

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