Propionic 2-hydroxy-3-nitro

Abbreviations N-methyl-D-aspartate (NMDA), alpha-amino-3-hydroxy-5-methyl-4-isoxazole-propionic acid (AMPA), L(+)-2 amino-3-phosphonopropionic acid (L-AP3), 6-cyano-7-nitroqninoxaline (CNQ5Q, 2,3-dihydroxy-6-nitro-7-sulfamyl-benzo-f-quinoxaline (NBQX), 3-(2-carboxypiperazin-4-yl)-propyl-l-phosphonic acid (CPP), 7 Chlorokynnreic... 

Propionic, butyric, and isobutyric acids have been prepared in better than 90% yields by heating the corresponding nitro compounds for 8 hours at 120-140° with 85% sulfuric acid. ° The reaction may be stopped at the hydrozamic acid stage by using milder conditions. This peculiar rearrangement of the nitro compound to the hydrozamic acid has been reviewed. a-Nitroolefins are hydrolyzed to a-hydroxy acids. ... 

Study of the metabolism of dinoseb and its acetate and of binapacryl in rabbits showed that 2-amino-6-sec-butyI-4-nitrophenol (39) is formed aiid excreted as O-conjugate with glucuronic acid, glucuronide (40). In rats this metabolism appears only in traces, but for both compounds the oxidation of the side chain — and thus the formation of -methyl-/ -(2-hydroxy-3,5-dinitrophenyl)propionic acid (41) in considerable quantities, also excreted in the urine — has b n detected. The evacuation of nitro compounds from warm-blooded organisms is relatively slow. 

This method was first applied by Weisbalt 135) to the synthesis of ethyl a-hydroxyamino-a-carboethoxy-P-(3-indole)-propionate. The reduction of nitrohydantoins (72) with zinc dust in the presence of ammonium chloride 136,137) or isopropylamine hydrochloride (97) was the basis for the first syntheses of N -hydroxyomithine (73) and N -hydroxylysine (74), but gave only low yields (Scheme 20). Further attempts at synthesis of N -hydroxyornithine (73) 138) and N -hyd-roxylysine (74) 139) based on such reductions were unsuccessful. The conditions for reduction of nitroester (75) to the ester of N-hydroxy-amino acid (76) were investigated by CfflMiAK 80), who obtained (78, 79) in aqueous methanol solution. Shin 140) also reduced nitro-esters (75) to (76, 77) using aluminium amalgam (Scheme 21). 

Pyrrolidones. A soln. of 2 g. 3-j -hydroxy-17j5-nitro-17a-(2-carbomethoxy-ethyl)-5-androstene 3-acetate in glacial acetic acid stirred and refluxed 72 hrs. with Zn-dust added at 24 hr. intervals 1.6 g. 3-(3j5-hydroxy-17/5-amino-5-androsten-17a-yl) propionic acid lactam 3-acetate. F. e. s. A. A. Patchett et al., J. Org. Chem. 27, 3822 (1962). 

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