Methoxyamine hydrochloride

Cheney et al. (1995) analyzed steroids by coupling an HPLC purification step with GC/MS. The steroids were initially characterized by their HPLC retention times compared with the retention times of tritium-labeled recovery standards. Next, the nemosteroids were characterized by their GC retention times. Finally, they were identified by their unique fragmentation spectra following derivatization with heptafluorobutyric anhydride or methoxyamine hydrochloride. For structmal identification, the mass spectra were compared to appropriate reference standards. This approach is highly specific, and its sensitivity is increased by the use of SIM. The detection limit for measuring allopregnanolone achieved in the 1995 study was 0.63 pmol (0.2 ng) starting from 100-300 mg of brain tissue. 

Methoxyamine hydrochloride [593-56-6] M 83.5, m 151-152°. Crystd from absolute EtOH or EtOH by addition of ethyl ether. [Kovach et al. JACS 107 7360 1985],... 

Gas Chromatography-Mass Spectrometry. Prepare methoxime derivatives by heating the extract from the thin-layer chromatographic plate with 100 xl of an 8% solution of methoxyamine hydrochloride in dry pyridine at 60° for 30 minutes, and evaporate in a rotary film evaporator. Silylate by dissolving the residue in 100 Lll of chloroform, adding 100 Lll of A,0-bis(trimethylsilyl)acetamide and 20 Lll of trimethylchlorosilane, then seal, and heat for 2 hours at 60°. When only 5a-estrane-3P,17a-diol is to be confirmed the methoxime formation can be omitted. Prepare a 2-cm column of Sephadex LH-20 in a Pasteur pipette with a cotton wool plug, using a... 

The dimethyl 2-methoxycarbonyl-2-(methoxyimino)ethylphosphonate used in the Homer-Wadsworth-Emmons reaction as an amino acid synthon is prepared by masking the carbonyl group of methyl bromopymvate with methoxyamine hydrochloride before submission to a Michaelis-Arbuzov reaction with trimethyl phosphite (Scheme 8.37).5 "5 By contrast, unprotected 3-benzoyl-... 

Treatment of 11 with methoxyamine hydrochloride in pyridine afforded the oxime 23, which was oxidized with chromium trioxide in pyridine to afford the ketone 24 (Scheme... 

In the second method, which appeared to be superior, the 17a-ethynyl side-chain was first introduced by reaction of (11) with lithium or potassium acetylide in liquid ammonia, and the resulting product was treated with methoxyamine hydrochloride in pyridine solution to give the ether oxime (13). Finally, conversion into norgestrel (14) was effected by chromium trioxide oxidation in dimethylformamide (DMF), followed by acid treatment. 

SYNTHESIS To a solution of 20.9 g methoxyamine hydrochloride in 75 ml MeOH (a strongly acidic solution) there was added 4.45 g 3,4-methylenedioxyphenylacetone (see under MDMA for its preparation) followed by 1.10 g sodium cyanoborohydride. There was the immediate... 

Methoxyimino-ketones are not only variants of the 1,3-dicarbonyl group, but also they have the advantage of affording excellent regioselectivity for the pyrazole formation. Chemoselective condensation between the diketoester and methoxyamine hydrochloride produced... 

Methoxy-4-allylphenol. See Eugenol Methoxyamine, hydrochloride. See o-Methylhydroxylamine hydrochloride 2-Methoxy-1-aminobenzene. See o-Anisidine 4-Methoxy-1-aminobenzene. See p-Anisidine 2-Methoxy-1-aminobenzene hydrochloride. See o-Anisidine hydrochloride 4-Methoxy-1-aminobenzene hydrochloride. See p-Anisidine hydrochloride 6-Methoxy-2-aminobenzothiazole. See 2-Amino-6-methoxybenzothiazole... 

In a useful variant, it was demonstrated that nicotinic acid derivatives 90 can also be accessed (10CEJ428, 10EJO6582).The use of primary amines with good leaving groups attached to the nitrogen enables a subsequent elimination with formation of the pyridine core. This was realized using methoxyamine hydrochloride and sodium acetate in ethanol or iso-propanol at elevated temperatures in a microwave apparatus (Scheme 31). 

The Methoxymation Reaction Methoxyamine hydrochloride should be dissolved in pure pyridine at a concentration of 20 mg/mL at room temperature (between 20 and 25°C). The reagent has to be prepared freshly just before the experiment. 

OMethylhydroxylamine hydrochloride Methoxyamine hydrochloride CHeCINO 593-56-6 83.518 pr 150.0 vs HjO, EtOH... 

Lauryl amine hydrochloride 4642 Mellitene 5813 Methoxyamine hydrochloride 7372... 

For the analysis of volatile compounds the sample material, for example rice or leaves are weight in equal amounts into headspace vials and capped. For the analysis of the extracted metabolites plant material (leaves) gets homogenized under liquid nitrogen. About 50 mg are applied to extraction with a water/chloroform/methanol mixture to extract water soluble metabolites. The polar phase is dried in a vacuum centrifuge. A 2-step derivatization can be applied First a methoxyamination (methoxyamine hydrochloride in pyridine)... 

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