DL-Omithine

The N,0-acetals are intermediates for the synthesis of enamides 264) and for the production of DL-omithine 265 266) and DL-lysine 267 268>. The amino acid syntheses are not economically competitive with the fermentation methods since they only give the racemates, which then have to be resolved into the antipodes. 

Poly(D,L-omithine hydrobromide) X2682-33-5 DL-Omithine, homopolymer, hydrobiomide R (C5H,2N202)r jcBrH... 

Eng-Wihnot DL, Rahman A, Mendenhall JV, Grayson SL, van der Hehn D (1984) Molecular Structure of Eerric Neurosporin, a Minor Siderophore-hke Compound Containing iV -hydroxy-D-omithine. J Am Chem Soc 106 1285... 

Properties (L(+)-omithine.) Crystals from alcohol-ether. Mp 140C. Soluble in water and alcohol, (dl-ornithine) Crystals from water. Slightly soluble in alcohol. 

To obtain a maximum yield of dl-lysine, the keto ester is allowed to react with hydrazoic add in the presence of a stream of hydrogen chloride the reaction mixture is then hydrolyzed and evaporated to remove the hydrochloric acid, and the residue is treated with hydrazoic acid and concentrated sulfuric acid. In a similar manner, ethyl cyclopentanone-2-carboxylate yields a-aminoadipic acid and dZ-omithine. 

Abbreviations ADC, arginine decarboxylase ODC, ornithine decarboxylase SAM, 5-adenosylmethionine DFMA, DL-a-difluoromethylaiginine DFMO, DL-a-difluoromethyl-omithine MGBG, methylglyoxal bis(guanylhydrazone) DCHA, dicyclohexylamine. 

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