Reaction of chlorine fluosulfate with perfluorocarboxylic acid nitriles

Conclusions The reaction of chlorine fluosulfate with perfluorocarboxylic acid nitriles, using an equimolar ratio of the reactants and the corresponding order of mixing them, gives N-chloroiminoperfluoroacyl fluosulfates in high yield, while the use of excess chlorine fluosulfate gives perfluoroacyl fluosulfates and pyrosulfuryl difluoride.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2370–2373, October, 1981.     

Acylation of hydrazides with acetic acid and formic acid

In peptide synthesis, hydrazides are important intermediates for the azide coupling method. A hydrazide is converted to the corresponding azide in the presence of an acid and a nitrite. When acetic acid (or formic acid) is used as the acid, partial acetylation (or formylation) of the hydrazide occurs as a side reaction. Formylation of the hydrazide is much faster than acetylation. Removal of the formyl group on the hydrazide with hydrazine and hydroxylamine was studied. The rate of deformylation with hydrazine treatment is faster than that with hydroxylamine treatment.     

Reaction of acid hydrazides with some thiazolidones

Thiazolidone 4-acylhydrazones are obtained by reaction of hydrazides of aromatic, aromatic sulfonic, and aliphatic acids with 4-thiono- and 4-imino-2-thiazolidones. The reaction of aliphatic hydrazides with 4-thiono-2-thiazolidone gives 4,4-azino-2-dithiazolidone. Condensation of 4-imino-2-thiazolidone with formylhydrazine gives pyrazolo[3,4-d]-2-thiazolidinone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1351–1353, October, 1973.     

The reaction of carboxylic acid hydrazides with formaldehyde

The hydrazides of benzoic, phenyacetic, and 3-phenylpropionic acids react with an acidic solution of formaldehyde to give 15 . Similar treatment of the corresponding methylhydrazides gave 16 . The ethers 15 can be cleaved to give, after methylation, 16 . Spectral data for 15 and 16 are presented.     

Catalytic thiomethylation of carboxylic acid hydrazides

Thiomethylation of carboxylic acid hydrazides with dimethylaminomethyl sulfides RSCH₂NMe₂ yielded the corresponding N′,N′-bis(sulfanylmethyl)carbohydrazides. When bis-sulfides Me₂NCH₂S(CH₂) _n SCH₂NMe₂ (n = 2–4) are used for thiomethylation, N-(acylamino)-substituted 1,5-dithia-3-azacycloalkanes are formed. These compounds can also be synthesized by CuCl₂·2H₂O-catalyzed thiomethylation of carboxylic acid hydrazides with either CH₂O and thiols or α,ω-alkanedithiols.     

Structural characteristics of some mercaptoacetic acid hydrazides

NMR and molecular modeling were used to analyze the conformational states of a series of mercaptoacetic acid hydrazides. A chemical exchange phenomenon was observed in the phase-sensitive NOESY spectrum of all derivatives in both CDCl₃ and DMSO-d6 solvents. Chemical shifts, temperature and solvent dependence as well as MonteCarlo conformational search suggest that two rotamers exist around the amide bond in solution in a slow, for the NMR time scale, interconversion at room temperature. The trans conformer is predominant in CDCl₃ and seems to be stabilized by the presence of hydrophobic interactions between the two aliphatic ends of the molecule. The relative population of the cis conformer increases tenfold in DMSO-d6 stabilized through the formation of hydrogen bonds.     

Structure of trimethylsilyl derivatives of acetic acid hydrazides

Conclusions ¹⁷O and¹⁵N NMR spectroscopy was used to show that the trimethylsilylated N,N-dimethylhydrazide of acetic acid is an equilibrium mixture of the syn and anti isomers of the hydrazone form, while the N.N'-bis-trimethylsilyl-N'-methylhydrazide of acetic acid exists as an equilibrium mixture of N and O isomers ( ₂₉₈ = 15.4 kcal/mole).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 2, pp. 464–466, February, 1985.The authors express their gratitude to E. N. Medvedeva and V. A. Lopyrev for providing samples of (I).     

Reactions of derivatives of phosphorylacetic acid hydrazides with 3,5-di-tert-butyl-4-hydroxybenzyl acetate

Abstract

To obtain new polyfunctional inhibitors of radical-chain oxidative processes, C- and N-benzylation of a number of phosphorylacetic acid hydrazide derivatives is realized in their reactions with 3,5-di-tert-butyl-4-hydroxybenzyl acetate. N-benzylation of mixtures of Z and E isomers of hydrazones of phosphorylacetic acid derivatives proceeds stereoselectively with the formation of only E_C=N isomers.     

A new procedure for preparation of carboxylic acid hydrazides

The standard method for preparing carboxylic acid hydrazides is hydrazinolysis of esters in alcoholic solutions. However, when applied to alpha,beta-unsaturated esters, the main product typically is the pyrazolidinone resulting from an undesired Michael-type cyclization. Other alternative methodologies reported for direct preparation of hydrazides from acids are inefficient. We developed an efficient and general process, involving preforming activated esters and/or amides followed by reaction with hydrazine, for the preparation of hydrazides including those of alpha,beta-unsaturated acids. This process gives the desired hydrazides in excellent yield and purity under mild conditions.     

Synthesis of conjugates of glyco amino acids and glycopeptides with carboxylic acid hydrazides

It is proposed to use a hydrazine bridge for obtaining conjugates of glycopeptides with biologically active carboxylic acids. Diacylhydrazines have been synthesized from glucofuranosylglycoloyl-L-alanine and -butylmuramoyltripeptide.Simferopol' State University, 333036, Ukraine, Crimea, Simferopol', ul. Yaltinskaya, 4. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 731–734, September–October, 1997.     

Antimycobacterial and anticancer activity of newly designed cinnamic acid hydrazides with favorable toxicity profile

A series of twelve novel hybrids of cinnamic acid and thiocarbohydrazones were designed, synthesized in high yield using a simple coupling strategy via acid chlorides, and evaluated for their impact against Mycobacterium tuberculosis (Mtb) and cancer cells survival. Among them, compound 3 demonstrated strong anti-Mtb activity by reducing bacilli survival for>90 % in all three treated Mtb isolates, whereas isoniazid and rifampicin did not. Moreover, compound 3 didn’t affect vitality of HepG-2 cells, implying on advantageous hepatotoxicity profile compared to current therapeutic options for tuberculosis. Compounds 2a and 3b displayed as strong inducers of apoptosis in A549 cells, both activating intrinsic caspase pathway and cell cycle arrest at the G0/G1 phase. Subsequent analyses disclosed differences in their activities, where 3b has ability to induce production of mitochondrial superoxide anions, while 2a significantly inhibited cellular mobility. More importantly, 3b considerably affected viability of HepG-2 and HaCaT cells, whereas 2a had moderate impact only on the later. Molecular modeling studies indicated high permeability and good absorption through the human intestine, and moderate aqueous solubility with poor blood–brain barrier permeability. In summary, our results reveal that novel compounds 3 and 2a represent promising agents for tuberculosis and cancer treatment, respectively, indicating that further investigation needs to be performed to clarify the mechanisms of their anti-Mtb and anticancer activity.     

Copper(I)-picolinic acid catalyzed N-arylation of hydrazides

An efficient copper-catalyzed carbon-nitrogen bond formation is described. The copper(I) complex with commercially available 2-picolinic acid ligand was found to be effective in N-arylation of N-Boc-hydrazine. This methodology offers a regioselective N-arylation of hydrazides using a variety of substituted aryl iodides.     

Complexation of calix[4]resorcinol with phosphorylacetic acid hydrazides possessing neurotrophic activity

The structures of the molecular complexes based on calix[4]resorcinol bearing a p-tolyl moiety at the lower rim with phosenazid (2-(diphenylphosphoryl)acetohydrazide) and CAPAH (2-{[4-(dimethylamino)phenyl](2-chloroethoxy)phosphoryl}acetohydrazide) were studied by NMR, IR, and UV spectroscopy and X-ray powder diffraction. The results of the screening of neurotrophic activities of the molecular complexes are presented.

     

The reaction of optically active α-aminocarboxylic acid hydrazides with triethyl orthoesters

New derivatives of 2-(1-amino-1-phenylmethyl)-1,3,4-oxadiazole and 1,2,4-triazin-6-one were synthesised in the reactions of optically active α-aminocarboxylic acid hydrazides and triethyl orthoesters in xylene. The electronic and steric effects of substituents at the α position influencing the formation of five- or six-membered products are discussed.     

Gas-liquid chromatography of perfluorocarboxylic thioesters

Perfluorocarboxylic thioesters R_FC(O)SR (R_F=CF₃(CF₂)_j, R=CH₃(CH₂)_i, i andj=0–5) were studied for the first time by GLC on packed columns using SE-30, SKTFT-50X, and XE-60 as the stationary phase. The values of thermodynamics functions of sorption were calculated. The correlations between these functions and the molecular structures as well as the conditions of analysis were established. The insertion of the S atom into the molecules of derivatives of perfluorocarboxylic acids causes a decrease in the contribution of the orientation interaction and an increase in the dispersion interaction of thioesters with the stationary phases compared to esters and amides of perfluorocarboxylic acids studied previously. For Part 1, see Ref. 1. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1165–1168, June, 1997.     

Hexacyanoferrate(III) oxidation of n-valeric and iso-valeric acid hydrazides in perchloric acid

Summary The kinetics of the title reaction were determined spectrophotometrically. The oxidation was second order; but first order with respect to both [hexacyanoferrate(III)]₀ and [hydrazide]₀. The effect of [HClO₄] on the reaction rate was curious; as the HClO₄ concentration increased the rate decreased and, reaching a minimum. The rate was slightly enhanced by an increase in ionic strength, but was insensitive to added salts, such as NaClO₄, NaNO₃, NaCl, KCl, Licl and K₄Fe(CN)₆ at constant ionic strength. Addition of MeOH retarded the oxidation rate and the entropy of activation was negative. Carboxylic acids and N₂ were identified as the oxidation products. A radical mechanism and a rate law consistent with the experimental results is proposed.