2-Amino-4-hydroxy-4-nitro

Durch Erhitzen von aromatischen Sulfonsaure-(hydroxy-aniliden) in verdunnter Kalilauge oder mit Kaliumhydroxid in Dimethyl-sulfoxid erhalt man Amino-hydroxy-biphe-nyle z. B. 2-Amino-4-hydroxy-4 -nitro-biphenyl (80%)3 ... 

Thiazole, 5-amino-4-ethoxycarbonyl-2-methyl-synthesis, 6, 306 Thiazole, 2-amino-4-(2 -furyl)-bromination, 6, 256 Thiazole, 2-amino-4-hydroxy-synthesis, 6, 296 Thiazole, 5-amino-2-hydroxy-synthesis, 6, 301 Thiazole, 5-amino-2-mercapto-synthesis, 6, 301 Thiazole, 2-amino-4-methyl-alkylation, 6, 256 synthesis, 6, 300 Thiazole, 2-amino-5-nitro-antiparasitic activity, 1, 180... 

Die praparativ bedeutende Reduktion von Carbonsaure-estern zu Alkoholen mit Hy-drideii verlauft gut und ohne Nebenreaktionen auch in den Fallen, wo die klassischen Me-thoden (metallisches Natrium in Alkohol nach Bouveault-Blanc, katalytische Druckhy-drierung) versagen, z.B. bei Halogen-, Hydroxy-, Nitro- und Amino-carbonsaure-estern, bei Polyen-carbonsaure-estern und bei enolisierbaren Carbonsaure-estern. 

Hydriert man 6-Acetylamino-4-hydroxy-7-(N-methyl-N-nitro-amino)-8-nitro-chinazolin, so wird die aromatische Nitro-Gruppe reduziert und die N-Nitro-Bindung gespalten. Bei der Zu-gabe von konzentrierter Salzsaure tritt Cyclisierung zu 9-Amino-1,2-dimethyl-5-hydroxy-lH-<,imidazo[4,5-g]chinazolin)-Hydrochlorid (80% Schmp. 326-327°) ein131 ... 

Die Bestrahlung von Azobenzolen in Anwesenheit von Sauerstoff fiihrt zu unterschied-lichen Resultaten. 4-Arylazo-l-hydroxy-naphthaline liefern nur 1,4-Naphthochinon. Kei-nerlei Oxidationsprodukte werden bei 4-Amino-4 -nitro-azobenzol erhalten. 4-Dimethyl-amino-2/,4 -dinitro-azobenzol liefert in 35-40% Ausbeute l-(4-Dimethylamino-phenyl)-2- (2,4-dinitro-phenyl)-diazen-l-oxid2. 

Weak Medium 300 1 15 Alcohols, phenols, and intermolecular hydroxyl to carbonyl bonding <100° 10 100-300 50 1.2- Diols, a- and most /3-hydroxy ketones o-chloro and oal-koxy phenols 1.3- Diols some /3-hydroxy ketones /3-hydroxy amino compounds /3-hydroxy nitro compounds... 

Nitroaminobydroxybenzoic Acids,C7HSN2 Os, mw 198.13, N 14.14%. The following isomers are described in the literature 3-amino-5-nitro-4-hydroxy- and 3-amino-6-nitr0-4-hydroxy-benzoic acids. 

Six membered heterocyclics can be synthesized in various ways. Nitrogen analogues of stilbene, like the anilides of benzaldehyde or acetophenone sometimes form azaphenanthrenes 19). Similarly the plasma reaction of azobenzene yields a small amount of diazaphenanthrene 19>. Better results are observed in the cyclization of hydroxy, amino or nitro compounds. Suitable starting materials are molecules with two phenyl groups linked by a carbon or hetero atom. 

Prior to the discovery of a-sulfonation of anthraquinone, nitration was the only useful method for preparing a-substituted anthraquinones. The nitro group of a-nitroanthraquinones can be replaced in a manner similar to the sulfonic acid moiety, e.g., by chlorine atoms and amino, hydroxy, alkoxy, or mercapto groups. Reduction readily yields aminoanthraquinones. Nitration of anthraquinone has gained increasing importance because of environmental considerations, this method offering an economical alternative to a-sulfonation... 

Aminophenols which were formerly obtained only by the reduction of nitro-compounds in concentrated sulphuric aoid can now be prepared by reducing dilute acid suspensions of nitro-compounds, provided the mixture be well stirred and the cathode surfaces made up. of two or more metals. This improved process, which it is claimed gives good yields of amino-hydroxy bodies, is due to the Society of Chemical Industry, Basle.1 When an indifferent cathode is employed, the addition of certain metals in the form of salts or finely powdered metal to the electrolyte increases the yield of amine at the expense of amino-hydroxy compound such are copper, iron, or lead if added separately. If, however, two at least of these and other metals be added, reduction to aminophenol is favoured. 

Aminoindoxazenes, which are stable towards acids and bases, can be diazotized in acetic acid Lindemann and Ciss e46,70 reported the conversion of 3-amino-5-nitro- and 3-amino-5-acetamido-indoxazenes into the corresponding 3-hydroxy compounds (indoxazenones), via the diazonium salts. Attempts to prepare 3-hydroxyindoxazene and its 6-chloro derivative by the same route were unsuccessful.46 The structures of these 3-hydroxy compounds would seem doubtful since Boshagen reports a much higher melting point for 3-hydroxy-5-nitro-indoxazene (223.5,46 85-88°,70). 

Phosphoranes are reactive towards all types of aldehydes and ketones (aldehydes are much reactive than ketones). Generally, no reaction occurs with nitriles, esters, amides, nitro, amino, hydroxy, halogen and alkoxy groups. 

Pyridazine 4-Amino-5-nitro-3-phenyl- E9a, 617 (H -> NH2) Pyrido[2,3-d pyrimidin 6-Cyan-4-hydroxy-7-methoxy-2-methyl-E9c, 93 [2-NH2 —3-(CO—... 

Reaction of the Titanated Bislactim Ether. The titanium derivative of the bislactim ether of cyclo(L-Val-Gly) reacts with alkyl aldehydes, aryl aldehydes, and a,(3-unsaturated aldehydes highly diastereoselectively to give almost exclusively the syn addition products (eq 2). Hydrolysis with dilute Trifluo-roacetic Acid affords (2R, 35 )-(3-hydroxy-a-amino acid methyl esters. a-Amino-y-nitro amino acids can be obtained by 1,4-addition of the titanated bislactim ether to nitroalkenes and subsequent hydrolysis of the adduct. ... 

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