Biosynthesis of Nitro Compounds. II. Studies on Potential Precursors for the Nitro Group of β-Nitropropionic Acid*

Biochemistry ◽  
1967 ◽  
Vol 6 (7) ◽  
pp. 2247-2253 ◽  
Author(s):  
Paul D. Shaw ◽  
James A. McCloskey
Keyword(s):  
Nitro Group ◽  
Nitro Compounds ◽  
Nitropropionic Acid

Toxicological investigations on Astragalus hamosus and Astragalus sesameus

1980 ◽  
Vol 20 (103) ◽  
pp. 162 ◽  
Author(s):  
MC Williams
Keyword(s):  
Nitro Compounds ◽  
Aliphatic Nitro Compounds ◽  
Water Extracts ◽  
Nitropropionic Acid ◽  
3 Nitropropionic Acid

Astragalus hamosus L. and Astragalus sesameus L. were examined for the presence and type of aliphatic nitro compounds and for their toxicity to 1 -week-old chicks. A. hamosus leaves assayed 10 to 11 mg of NO2 g-1 in compounds that yielded 3-nitropropionic acid upon hydrolysis. Water extracts of A. hamosus leaves were toxic to chicks at the equivalent of 3 g of dried plant per chick, and lethal at 6 to 8 g. A. sesameus did not contain nitro compounds and was non-toxic to chicks.

Simple Synthesis of Dimethyl Nitrobenzhydrylphosphonates and Heteroarylnitroarylacetonitriles via Vicarious Nucleophilic Substitution (VNS) Reaction

Synthesis ◽  
2020 ◽  
Vol 53 (01) ◽  
pp. 175-181
Author(s):  
Mieczysław Mąkosza ◽  
Małgorzata Bechcicka ◽  
Krzysztof Wojciechowski
Keyword(s):  
Nucleophilic Substitution ◽  
Nitro Group ◽  
Nitro Compounds ◽  
Simple Synthesis ◽  
Para Position ◽  
Crucial Step ◽  
Vicarious Nucleophilic Substitution ◽  
Aromatic Nitro Compounds ◽  
Leaving Group ◽  
Aromatic Nitro

Acetals of dimethyl phenyl- and heteroaryl-α-hydroxymethanephosphonates were deprotonated to generate carbanions, which enter the vicarious nucleophilic substitution (VNS) of hydrogen in aromatic nitro compounds to form 4-nitrobenzhydrylphosphonates and α-heteroaryl-4-nitrobenzylphosphonates. Similarly acetals of cyano­hydrins of heteroaromatic aldehydes (furfural and 2-formylthiophene) react to form heteroaryl 4-nitroarylacetonitriles. The anion of the hemiacetal of acetaldehyde is an efficient leaving group in the base-induced β-elimination step – the crucial step in the VNS reaction. The reaction selectively occurred at the para-position to the nitro group.

The possibilities of polarography in the chemistry of nitroazoles

1984 ◽  
Vol 49 (6) ◽  
pp. 1342-1353 ◽  
Author(s):  
Dragica Dumanović ◽  
Janka Ćirić ◽  
Djuro Kosanović ◽  
Dragoslav Jeremić
Keyword(s):  
Nitro Group ◽  
Systematic Investigation ◽  
Nitro Compounds ◽  
The Other ◽  
Polarographic Method ◽  
Spectrophotometric Methods ◽  
Group Position ◽  
High Yields

Based on systematic investigation of mononitroimidazoles, selective polarographic and spectrophotometric methods for determination of nitrazole compounds in reaction mixture are proposed. It was proved that the selectivity is based on the different properties of the nitro group due to the effects of the nitro group position in the ring, the type and position of the other substituents and on the fact whether the compound is N-substituted or not. The proposed methods can be successfully used for monitoring the synthetic procedures and decreasing the number of experiments for optimization. Based on the anticipated and proved behaviour of the nitro compounds of pyrazole, novel mononitropyrazole derivatives were synthetized in a new way and with high yields. Applying the polarographic method it was discovered that during N-substitution of tautomeric mononitroimidazole and mononitropyrazole substrates other byproducts were obtained besides the main products and undesired isomers. The products were identified and then a correct and more complete N-substitution scheme could be given. Following quantitatively these N-substitution processes conclusions which directly concern the mechanism of reactions were drawn.

Investigation of Correlation between Impact Sensitivities and Nitro Group Charges in Nitro Compounds

2005 ◽  
Vol 109 (18) ◽  
pp. 8978-8982 ◽  
Author(s):  
Chaoyang Zhang ◽  
Yuanjie Shu ◽  
Yigang Huang ◽  
Xiaodong Zhao ◽  
Haishan Dong
Keyword(s):  
Nitro Group ◽  
Nitro Compounds ◽  
Impact Sensitivities

Studies on the rearrangement of ortho-nitrobenzylidenemalonates and their Analogues to 2-aminobenzoate derivatives

2002 ◽  
Vol 80 (2) ◽  
pp. 192-199 ◽  
Author(s):  
Elzbieta Lewandowska ◽  
Stefan Kinastowski ◽  
Stanislaw F Wnuk
Keyword(s):  
Double Bond ◽  
Nitro Group ◽  
Phenyl Ring ◽  
Nitro Compounds ◽  
Trifluoromethyl Group ◽  
Reverse Polarity ◽  
Michael Reactions ◽  
Carbon Double Bond ◽  
Oxidative Rearrangement ◽  
Aromatic Nitro

Reaction of the diethyl 2-nitro-4-(trifluoromethyl)benzylidenemalonate with diethylamine in alcohols resulted in the reduction of the nitro group and the oxidation of the vinylic carbon attached to the phenyl ring. Simultaneous migration of the malonic fragment gave the appropriate 2-amino-4-(trifluoromethyl)benzoate esters. The presence of at least two nitro groups, or one nitro group and trifluoromethyl group on the phenyl ring, attached to the α-carbon and strongly electron withdrawing substituents at the β-carbon (CO2Et, CN) in ortho-nitrobenzylidene systems is necessary for this reductive–oxidative rearrangement to proceed. Reaction of nitrocinnamates with thiols in the presence of triethylamine in tetrahydrofuran gave Michael addition products with different regioselectivity of addition. Ethyl 2-nitrocinnamate undergoes standard β-addition of thiols to a carbon–carbon double bond. However, 2,4-dinitro- and 2,4,6-trinitrocinnamates undergo α-addition of thiols, indicating that the presence of two nitro groups on the phenyl ring can reverse polarity of the carbon–carbon double bond in cinnamate acceptors.Key words: abnormal Michael reactions, aromatic nitro compounds, benzylidene compounds, rearrangements.

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