Acid hydrazides, oxidation

Thiazole carboxylic acid hydrazides were prepared in a similar way (444, 445). Thus by refluxing thioacetamide or thiobenzamide with y-bromoaceto acetic ester arylhydrazones (83) for several hours in alcohol the 4-carboxythiazole derivatives (84) listed in Table II-ll were obtained (Scheme 36) (656). This reaction is presumed to proceed via dehydration of the intermediate, thiazoline-S-oxide. 

Furo[3,4-c][l,2,4]triazines 201 were prepared (75USP3962240 77USP-4013767) by condensing furandione 199 with the respective 2-aryl or pyri-dylcarboximidic acid hydrazide 200. Compound 201 (X = N) was oxidized to its N-oxide. Both 200 and 201 have sedative and tranquilizer properties (Scheme 42). 

Van Zyl JM, BJ van der Walt (1994) Apparent hydroxyl radical generation without transition metal catalysts and tyrosine nitration during oxidation of the anti-tubercular drug, isonicotinic acid hydrazide. Biochem Pharmacol 48 2033-2042. 

B. J. van der Walt, J. M. van Zyl, A. Kriegler, Different Oxidative Pathways of Isonicotinic Acid Hydrazide and Its Meta-Isomer, Nicotinic Acid Hydrazide , hit. J. Biochem. 1994, 9, 1081-1093. 

Oxidation of hydrazides. Acid hydrazides are oxidized to carboxylic acids by several Cu(I I) salts, particularly Cu(OH)2 and Cu(OH)CI. The salt can be used in calulytic amounts if oxygen is available to convert Ou(I) to Cu(II). For this purpose the most convenient salt is Cu(OAc), in THF or CH,OH (equation I). 

Solid-phase syntheses of triazines (Table 15.32) include the cyclocondensation of polystyrene-bound isothiuronium salts with /V-(cyano)iminodithiocarbonates and the cyclization with simultaneous cleavage from the support of derivatives of a-amino acid hydrazides (Table 15.32). (Benzylthio)triazines, such as those listed in Table 15.32 (Entries 1 and 2), have been cleaved from a support by oxidation to sulfoxides or sul-fones with N-benzenesulfonyl-3-phenyloxaziridine, followed by nucleophilic cleavage with primary or secondary aliphatic amines or with electron-rich anilines (see Section 3.8). 

Benzylidene thio cqrbazoyl Azide Benzalthio carbazinic Acid Azide or (N-Benzylidene-N -azidomercapto)-hydrazine (called Benzalthio-carbazinsaureazid by Stolle), CgHg.CH N.NH.C-( S).N3 mw 205.30, N 34.12% pale yel flakes, mp 173°, followed by an expl sol in hot ale or hot AcOH insol in w was prepd by shaking for 8 hrs a mixt of dithiocarbazinic acid hydrazide, Na azide Pb oxide in ale medium... 

Groups of reportedly photochromic systems which deserve further study include (a) disulfoxides (123,124), (b) hydrazones (125-129), (c) osazones (130-133), (d ) semicarbazones (134-143), (e) stilbene derivatives (144), (/) succinic anhydrides (145-148), and (g) various dyes (149,150). A number of individual compounds also remain unclassified as to their mechanism of photochromic activity. These include o-nitro-benzylidine isonicotinic acid hydrazide (151), 2,3-epoxy-2-ethyl-3-phenyl-1-indanone (152), p-diethyl- and p-dimethyl-aminophenyli-minocamphor (153), brucine salts of bromo- and chloro-nitromethionic acid (154), diphenacyldiphenylmethane (155,156), 2,4,4,6-tetraphenyl-1,4,-dihydropyridine (155,156), 2,4,4,6-3,5-dibenzoyltetrahydropyran (155,156), o-nitrobenzylidenedesoxybenzoin (157), p-nitrobenzylidene-desoxybenzoin (157), N-(3-pyridyl)sydnone (158,159), tetrabenzoyl-ethylene (160), and the oxidation product of 2,4,5-triphenylimidazole (161,162). 

Copper(II) acetate in methanol catalyzes the oxidation in air of acid hydrazides to carboxylic acids or esters (equation 2 88),621 and that of 1,2-dihydrazones to acetylenes (equation 289).61S... 

BODIPY 530/550 C3 hydrazide is 4,4-difluoro-5,7-diphenyl-4-bora-3a,4a-diaza-s-indacene-3-propionyl hydrazide, a derivative of the basic BODIPY structure, which contains two phenyl rings off the No. 5 and 7 carbon atoms and a propionic acid hydrazide group on the No. 3 carbon atom (Molecular Probes). The hydrazide functional group reacts with aldehyde- or ketone-containing molecules to form hydrazone linkages (Fig. 229). The compound may be used to label glycoproteins or other carbohydrate-containing molecules after oxidation of their polysaccharide portions with sodium periodate to yield aldehyde residues. 

Hydrolysis of 2-phenyl-[l. 2.3]triazolo[4,5-d]pyrimidine-5,7-dione N-oxides 463 in basic solution gives rise to 4-amino- and 4-ureido-2-phenyl-l,2,3-triazole-5-carboxylic acid 1-oxides 464, as well as their hydrazides and methylamide (2005JGU636) (Scheme 134). 

The reaction of isonicotinic acid hydrazide and corresponding benzaldehyde under microwave conditions gave the heterocyclyl acylhydrazones (xxi). The oxidation of xxi with iodobenzene diacetate (IBD) gave the heterocyclyl-1,3,4-oxadiazoles (xxii) in a solid state [29]. 

Oxidation of carboxylic acid hydrazides,7 Both aliphatic and aromatic carboxylic acid hydrazides are rapidly oxidized in good yield by CAN in aqueous acetonitrile to the parent acids. 

Adenosine triphosphate, when oxidized to its dialdehyde with periodate and condensed with Sepharose-adipic (or sebacic) acid hydrazide, has been used to isolate poly(A) polymerase, and also myosin and its fragments from different sources. A poly(A)-linked resin has been prepared by condensing 4,4 -diaminodiphenyl-methane with periodate-oxidized starch, reducing the resulting Schiff bases with borohydride, diazotizing, and then coupling with the polynucleotide. The resulting material may be used to isolate poly(U) sequences. 

Condensation of o-phenylenediamine with methylglyoxal, aldohexoses and aryl or alkyl acyloins gave the corresponding quinoxalines 76. Indoloquinoxalines were obtained from isatin. Carbethoxymethylation of isatin and then reaction with o-phenylenedimine gave the respective indoloquinoxalines 77, whereas hydrazide was condensed with aromatic aldehydes and monosaccharides. L-Ascorbic acid or D-isoascorbic acid were oxidized with iodine and then reacted with o-phenylenediamine and phenylhydrazine to give quinoxalinones 78, which were cyclized to pyrazolyl-quinazolinones . ... 

A solution of 1.6 g. of 1-methyl-ergotamine hydrochloride in 6.4 cc. of anhydrous hydrazine are heated for 1 hour at 90°, the mixture diluted with 50 cc. of water, the water and the hydrazine hydrate are distilled off and after the addition of a further 6.4 cc. of anhydrous hydrazine the remaining procedure is repeated. The residue is then shaken between a diluted tartaric acid solution and chloroform. The bases liberated after the tartaric acid solution has been made alkaline are shaken with chloroform and the crude product remaining after evaporation of the chloroform is chromatographed on a column of 25 g. of aluminium oxide. l-methyl-c -iso-lysergic acid hydrazide is washed into the filtrate with chloroform containing 0.5% of ethanol. The compound crystallizes from ethanol in the form of nice leaflets. Melting point 201-204°. [a]D20=+400° (c.=0.5 in pyridine). Keller s colour reaction blue. 

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