Chemical Journal of Kazakhstan

INVESTIGATION OF ELECTROCHEMICAL CHARACTERISTICS OF INTERGEL SYSTEMS BASED ON POLYACRYLIC ACID

Meruyert Suleimenova — 2024-03-31

Abstract. Introduction. Currently, hydrogels are polymer materials in high demand due to their
physicochemical properties, and recent years have seen significant attention given to the study of their
physicochemical properties [1,2]. The purpose of this research is to investigate the effect of remote
interaction on the electrochemical properties of intergel systems containing hydrogels of polyacrylic acid,
poly-4-vinylpyridine, poly-2-methyl-5-vinylpyridine, and polyethyleneimine hydrogels with various
initial states. The dependency of conductivity and pH levels in aqueous solutions of intergel systems was
examined. The obtained results have shown thatin the 5:1 ratio of the PAAswollen:P4VPdry intergel system,
the conductivity of the aqueous medium reaches its maximum value after 24 hours, with a corresponding
decrease in pH level. For the PAAdry:P2M5VPdry hydrogels at ratios of 5:1, 1:5, and 2:4, the high
electroconductivity was observed at the sixth hour. The maximum pH value was achieved at a ratio of 4:2,
indicating a low presence of nitrogen heteroatoms in the aqueous solution. The maximum conductivity in
the PAAswollen:PEIswollen system at a 3:3 ratio was reached after 8.5 hours, while the pH showed its
minimum value. In the study of the PAAdry:PEIdry intergel system, the pH of the aqueous medium
decreased over time in all hydrogel ratios. An exception was noted at a 4:2 ratio, where pH slightly
increased after 0.5 hours, then fell again, showing a deviation from the general pH trend. Conclusion. The
conducted research has shown that specific conductivity varies across all molar ratios of hydrogels. It was
established that changes in pairs and states of hydrogels in the intergel system affect specific conductivity,
indicating the ratio of ionized and dissociated groups in the chain changes normally. These results
demonstrate that these intergel systems can be used to get high-selectivity sorbents.

INFLUENCE OF ADDITIVE ON THE PROCESS OF PRODUCING PHOSPHORUS-CONTAINING COMPOSITE MATERIALS

Raushan Kaiynbayeva — 2024-03-31

Abstract: Introduction. The phosphorus industry of the Republic of Kazakhstan produces mineral fertilizers, as well as phosphate salts and multifunctional materials. Phosphate salts, including orthophosphates, pyrophosphates, triphosphates, polyphosphates, are effective anti-corrosion materials. The purpose of this work is to study the effect of additives on the production of phosphate-containing composite materials. Results and discussion. Analysis of the obtained results showed that the anticorrosion properties of compositions based on potassium dihydrogen monophosphate with the addition of potassium sulfate and boric acid are influenced by the same factors as in the case of individual salts. In tap water, the composition “KH₂PO₄ – K₂SO₄” is characterized by lower values of Vcor. and Vex. compared to the KН₂PO₄ – H₃BO₃ system. The degree of metal protection when adding potassium sulfate to tap water is 11.25% higher than when adding boric acid. However, in chloride-containing water, the nature of the additive does not affect the anti-corrosion properties of the composite system. The degree of protection in the studied compositions is almost the same (Z = 55.41-55.07%). It was revealed that in tap water in the “KH₂PO₄ – K₂SO₄/H₃BO₃ – H₂O” systems the degree of corrosion and deposits is noticeably lower compared to their values in a chloride-containing environment and, accordingly, the degree of protection in tap H₂O is (17.10-5.85)% higher compared to a chloride-containing environment . Conclusion. It has been shown that in tap water in the “KH₂PO₄ – K₂SO₄/H₃BO₃ – H₂O” systems the degree of corrosion and deposits is noticeably lower compared to their values in a chloride-containing environment, and accordingly, the degree of protection in tap H₂O is (17.10-5.85)% higher compared to a chloride-containing environment. When sulfate or borate ions are introduced into a solution, the rate of the iron ionization reaction in sulfuric acid can decrease, passivation of the metal occurs and the Z of the metal increases.

INFLUENCE OF LAYERED CONDUCTIVE COATINGS ON ELECTROCHEMICAL CHARACTERISTICS OF NaFe(SO4)2 CATHODE MATERIAL

Fyodor Malchik — 2024-03-31

Abstract: Introduction. Rising production and consumption, and the high cost of lithium salts
increased the price of lithium-ion batteries. Sodium-ion batteries are a promising replacement as safer and
cheaper. However, the cathode materials for these batteries have low conductivity, which critically
reduces their capacity. Modification with conductive additives is one way to solve this problem. Since a
large electronic contact area of the active material with the conductive coating is required, the main
candidates for such additives are materials with a layered structure. The purpose. To study the influence of
layered conductive additives on the performance and kinetic parameters of eldfellite-structured cathode
material. Methodology. By cyclic voltammetry and galvanostatic methods, it is found that as the 2D
material additive concentration increases, the active material’s performance characteristics initially
increase and then decrease, which is related to the sodium ions diffusion rate through the coating layer.
Results and discussion. As a result of the modification effect evaluation of NaFe(SO4)2 cathode material
with eldfellite structure by layered conductive coatings: graphite, molybdenum disulfide and MXene
(Ti3C2Tx), it was determined that for each material there is a certain optimal concentration at which peak
currents, capacitance and diffusion coefficient are maximized and resistance is minimized. The optimum
additive quantities are 0.5% for MoS2 and MXene, and 0.2% for graphite. Conclusion. The influence of
the concentration of 2D conductive coatings on the electrochemical properties of NaFe(SO4)2 intercalation
material is shown.

TECHNOLOGY FOR OBTAINING A DRY COMPLEX OF BIOLOGICALLY ACTIVE COMPOUNDS FROM A PLANT OF THE SPECIES ROSA BEGGERIANA SCHRENK

Balzhan Assetova — 2024-03-31

Abstract. Introduction. The study of medicinal plant raw materials as a source for the creation of
unique and highly effective medicines based on it is of great importance for the development of pharmacy
and medicine in Kazakhstan. Various types of rosehip contain a valuable complex of biologically active
compounds (BAC), which causes their widespread use in folk medicine due to antioxidant, antiinflammatory, choleretic and body-strengthening effects, as well as pharmacopoeial objects of both the
plants themselves and the medicines obtained on their basis. The object of this study – Rosa beggeriana
Schrenk, which grows only in Asia, in particular Kazakhstan, Iran, and some parts of China, and has an
almost unexplored valuable arsenal of compounds with biological activity, can increase the share of
domestic medicines in the pharmaceutical market of the country. Goals and objectives. The purpose is to
identify the suitability of raw material for further use in medicine. Research methods. The research object
was collected during the fruiting season along the Ili River in the Almaty region and dried in accordance
with recommendations for this type of raw material. In this study, chemical and physicochemical research
methods were used. The article presents data on the establishment of the goodness of the studied Rosa
beggeriana Schrenk plants and the dry complex of BAC obtained on a comparative context with the wellknown pharmacopoeia species of this plant family of Rosa canina plants, the mineral composition of
macro- and microelements and the development of an optimal technology for obtaining a complex of
biologically active substances from Rosa beggeriana Schrenk in the form of a dry extract. Conclusion. It
has been established that this type of rose hip can be used for medical purposes and is not inferior in
quality to the widespread type of rose hip Rosa canina. Parameters were also established under which the
highest yield of raw materials can be obtained.

INFLUENCE OF IONIC RADIUS ON THE DEGREE OF EXTRACTION OF RARE EARTH METALS DURING SORPTION BY THE INTERPOLYMER SYSTEM AMBERLITE IR-120 – AВ-17-8

Khuangul Khimersen — 2024-03-31

Introduction. Studies have been carried out on the sorption of rare earth metal ions in solution using the interpolymer system Amberlite IR-120:AB-17-8. The purpose of the work is to search for conditions for maximum sorption of rare earth elements (Dy, Tb, Gd, Eu and Sm) from aqueous solutions using the effect of remote interaction of ion exchange resins. Methodology. The residual concentrations of rare earth ions were determined using an Optima 8300DV Duo inductively coupled plasma spectrometer. Results. The best sorption characteristics were determined by the interpolymer system at a ratio of 3:3. The residual concentration of rare earth elements in the solution was: Dy – 4.64 mg/l, Tb – 4.16 mg/l, Gd – 4.21 mg/l, Eu – 4.16 mg/l, Sm – 4.56 mg/l. The variations in the ionic radius of the ions chosen for the study are Dy³⁺<Tb³⁺<Gd³⁺<Eu³⁺<Sm³+. The degree of sorption of interpolymer system increased with increasing ionic radius of the metals. For dysprosium with the smallest ionic radius, the degree of sorption was η – 52%, and for terbium, gadolinium and europium it increased to η – 58%. For individual Amberlite IR-120 (6:0), the degree of sorption of terbium ions was 47%. Conclusion. The results of the study showed that the interpolymer system with a ratio of 3:3 has the best sorption activity. It has been established that the degree of sorption of interpolymer pairs increases with increasing order of the ionic radius of metals (Tb³⁺< Gd³⁺< Eu³⁺).

SYNTHESIS AND CHARACTERIZATION OF N-ISOPROPYLACRYLAMIDE BASED COPOLYMERS WITH SILVER NANOPARTICLES

Ulantay Nakan — 2024-03-31

Absract: In recent years, the so-called "smart" polymers, which can systematically respond to small environmental changes, such as pH, temperature and electric field, are widely used in many fields. Researchers are particularly interested in using drugs to transport to the right place in the human body.

One of the types of these smart polymers are thermosensitive polymers. Among the thermosensitive polymers, the most well-known are homo- and copolymers based on N-isopropylacrylamide. In the research work, in order to improve the properties of thermosensitive polymers, silver nanoparticles were added to the hydrogel composition. Hydrogels based on N-isopropylacrylamide and 2-hydroxyethylacrylate monomers were synthesized by radical polymerization in solution (in H₂O and AgNO₃ solution).

While the production of silver nanoparticles is based on the redox (by NaBH₄solution) mechanism, the formation of these nanoparticles in the gel was carried out by diffusion. While the introduction of silver nanoparticles into the gel was controlled by ultraviolet spectroscopy, its inclusion in the gel was confirmed using a scanning electron microscope (SEM). Meanwhile, a hydrogel containing silver nanoparticles exhibits antibacterial properties, it was investigated using biomedical tests. It has been shown here that a hydrogel containing silver has good antibacterial properties, whereas a hydrogel without silver does not have the ability to destroy bacteria.

NEW POLYMERIC SORBENTS WITH THIACROWN-ETHER GROUPS

Kanat Sadykov — 2024-03-31

Absract: Introduction. The selectivity of compounds depends on the structure of the ligands in the
molecule, the presence of functional groups and donor atoms in it. It is known that the high selectivity of
the reagents depends not only on the nature of the donor atoms in the ring, but also on the stability of the
ring structure. The preparation of polymers containing a thiacrown ether group is an urgent task, since
such groups make it possible to obtain selective sorbents. The purpose of the work: is the synthesis of new
selective sorbents containing a thiacrown ether group and the study of their complexing properties with
respect to silver ions. Results and discussions: To obtain polymers for this purpose, the reaction of the
interaction of a gel and a porous copolymer of chloromethylated styrene and divinylbenzene with
aminobenzothiacrown ethers was studied. Using various influencing factors, it was possible to obtain
sorbents with a high exchange capacity (2.5 mmol/g). When studying the sorption of silver(I) ions from
aqueous solutions by a supramolecular sorbent with a thiacrown ether group, it was shown that the
optimal pH value is 6, the contact time is 60 min. The maximum sorption capacityof the sorbent for silver
(I) ions reaches 240.8 mg/g. Conclusion: Thus, the ability of the proposed polymer sorbents to
complexation depends on the ratio of reagents, the nature of the silver-containing reagent, the size of the
macrocycle and the dentinity of the ligand, which is determined by the amount of sulfur in thiacrown
esters.

STUDY OF THE CHEMICAL COMPOSITION OF THE RUBUS VULGARIS PLANT

Nazerke Bolatkyzy — 2024-03-31

Abstract. Introduction: Rubus vulgaris, a member of the Rosaceae family within the genus Rubus,
encompasses a diverse array of woody prickly plants characterized by their herbaceous multicolored or
often vertical growth habits, featuring climbing or elongated branches adorned with simple or complex
leaves. Among these species, Rubus vulgaris stands out as a shrub renowned for its prized fruits,
commonly referred to as blackberries. These fruits hold significant importance due to their multifaceted
utility in medicinal, cosmetic, and nutritional domains. Recognized as a concentrated source of valuable
nutrients and biologically active compounds with therapeutic potential, Rubus vulgaris earns recognition
as a functional food. The fruits and leaves of Rubus vulgaris harbor a rich reservoir of phenolic acids,
including ellagic, gallic, caffeic, and p-coumaric acids, alongside flavonoids such as quercetin,
hyperoside, kaempferol, myricitin, (+)-catechin, (–)-epicatechin, epicatechin gallate, procyanidin B2, and
quercetin-3-D-glucoside. This intricate chemical composition underscores the plant's significance in
various industries. Further analysis of Rubus vulgaris composition reveals its moisture content (6.71 %),
ash content (3.48 %), extractive substances (16.48 %), organic acids (1.43 %), flavonoids (0.23 %),
tannins (1.56 %), alkaloids (3.98 %), coumarin (2.18 %), saponins (3.80 %), and carbohydrates (2.12 %).
Additionally, employing multi-element atomic emission spectral analysis unveiled the presence of eight
elements in the plant ash, prominently featuring potassium (162 mg/g), calcium (29 mg/g), phosphorus
(22 mg/g), and magnesium (20 mg/g). Such comprehensive elucidation of Rubus vulgaris's chemical
composition not only underscores its nutritional significance but also paves the way for its utilization in
diverse fields ranging from pharmaceuticals to food science and beyond.

STUDY OF THE CHEMICAL COMPOSITION OF THE ACROPTILON REPENS PLANT

Moldyr Dyusebaeva — 2024-03-31

Abstract. Introduction. Creeping mustard (Acroptilon repens) is a perennial plant of the Asteraceae
family and is one of the most persistent and difficult to eradicate weeds. They are actively fighting it, but
the methods of combating it are very complex, high-cost and ineffective. Creeping mustard is used in folk
medicine to treat many diseases, but the phytochemical composition of this plant has not been sufficiently
studied. The purpose of this work: to study the chemical composition of this plant. This research will help
find new sources of biologically active substances (BAS), as well as solve the problem of clogging of
agricultural land. Methodology: generally accepted methods for determining the main biologically active
substances in plant materials, spectrophotometry, high-performance liquid chromatography (HPLC).
Results: the phytochemical analysis of the composition of Acroptilon repens collected in the Almaty
region was carried out. The results showed the following characteristics: moisture (11.4%), ash content
(6.21%), extractives (22.5%), organic acids (1.9%), flavonoids (3.75%), tannins (0.6%), alkaloids
(1.86%), coumarins (1.18%), saponins (2.47%), carbohydrates (2.5%). By multi-element atomic emission
analysis, 8 elements were identified in plant ash, with Mg (77.09 μg/ml), K (77.28 μg/ml), Na (34.075
μg/ml) and Ca (28.07 μg/ml) predominant in plant ash. Significant quantities of these elements indicate
the high physiological activity of creeping bitterweed. Additionally, a total alcohol extract was obtained
(96% ethyl alcohol was used), which was further divided into fractions using petroleum ether, hexane,
ethyl acetate and butanol. The ethyl acetate fraction was analyzed using HPLC. The results of the study
showed the presence of naringin in the ethyl acetate extract. Conclusion: The results obtained provide
important information about the chemical composition of the studied plant Acroptilon repens, which
contains a complex of biologically active substances, which may be useful for further scientific and
applied research.

ROLE OF THE SURFACE LAYER OF EPOXY RESIN

Elmira Kambarova — 2024-03-31

Abstract. Introduction. Water pollution threatens human health, and the safe supply of drinking
water has been recognized as a problem worldwide. The increasing accumulation of heavy metals in water
from various sources has led to the search for effective and environmentally friendly treatment methods
and materials for their removal. To impart the necessary characteristics to minerals, in particular to
improve sorption properties, one of the methods is modification. Modern technologies using sorbents
require qualitatively new sorption materials with increased capacity and high selectivity of action. Epoxy
resins are widely used as a base material in the coating field due to their advantages including adsorption
properties. In this work, shungite from the Koksu deposit and Shankhanai zeolite were used as natural
sorbents for modification. The purpose of this work is to study the interaction of epoxy resin ED-20 with
the surface of a natural sorbent through a layer of polyethylene polyamine. Methodology. To study the
surface of the prepared samples, methods such as infrared spectroscopy, gravimetry and the temperatureprogrammed desorption method were used. Results and discussion. This article presents the results of IR
spectroscopic analysis of natural sorbents shungite and zeolite modified with epoxy resin ED-20 and
polyethylene polyamine. The obtained surface epoxy layers were studied for resistance to aqueous
environments of varying acidity for 90 days. The acid-base properties of the surface layers of modified
sorbents were studied by the method of temperature-programmed ammonia desorption. Conclusion. By
modifying shungites and zeolites with polyethylene polyamine, followed by cross-linking them on the
surface of a natural mineral with ED-20 epoxy resin, a durable layer of epoxy resin was obtained.

SYNTHESIS AND PHYSICO – CHEMICAL CHARACTERISTICS OF COMPLEX FERRITE CrNaFe2O5

Altynai Madiyarova — 2024-03-31

Abstract: Introduction. The article discusses for the first time the synthesis, radiographic and electron
microscopic examination of CrNaFe2O5, synthesized using the high – temperature Sol-gel method. The
phase of complex ferrites was synthesized using Sol-Gel synthesis method at high temperature. Initially,
the structure of CrNaFe2O5 composite ferrite was researched by X-ray phase analysis and SEM, the
syngony type, elementary cell parameters, radiographic and pycnometric densities and elemental analysis
were defined: CrNaFe2O5 -а=5.0289, в= 5.0289, с=13.6938 Å , ρx-ray.= 5.327 g/sm3
, ρpycn.=5.331 g/sm3
. A
comparative analysis of the connection between the parameters of the Crystal cell of the initial materials
and of the obtained complex ferrites was carried out. Through a scanning electron microscope,
microsystems were taken from different parts of CrNaFe2O5 type crystallite, the elemental composition of
crystals was analyzed, and the general type of surface layer of complex ferrite was displayed. As a result,
the fact that the compound consists of a single phase, the clarity of its construction was determined by the
topography and chemical composition of the compound. Consequently, it was discovered that the newly
synthesized complex ferrites correspond to the formula CrNaFe2O5. The particles of the formed
compounds have a large size (between 200 µm, 20.0 µm and 5 µm). The results of the element analysis
show that the compound is compatible.

PREPARATION OF HYDROGELS BASED ON NATURAL POLYMERS FOR PELLETING OF SUGAR BEET SEEDS

Danelya Makhayeva — 2024-03-31

Abstract. Introduction. One of humanity`s important problems is the lack of water in arid regions. One of the ways to solve the water shortage problem is the use of seed pelleting technology. The polymer film coating contributes to the effective maintenance of their quality during storage, including humidity regulation. The creation of effective coatings based on biodegradable natural polymers will help preserve natural resources and prevent environmental pollution. The purpose of this work is the radiation synthesis and characterization of hydrogels based on natural and synthetic polymers and the search for optimal conditions for coating the seeds with the resulting polymers. The methodology of the work includes the radiation synthesis of hydrogels, physicochemical characterization by gravimetry, germination, and germination energy study of coated seeds. Results and discussion. Hydrogels based on chitosan, polyvinylpyrrolidone, starch, and agar-agar were obtained using the radiation. The optimal parameters are 25 kGy irradiation dose and 5wt.% starch concentration. The presence of agar-agar in the hydrogel composition and the increase of irradiation dose from 15 to 45 kGy boost the gel fraction yield. The work investigated the water-holding capacity of pelleted seeds and the process of water desorption from the polymer shell. It has been established that the polymer shell around the seed can retain water in the early stages of its development. Seeds coated in two layers retain moisture 7 times longer compared to uncoated samples. Conclusion. These results can be used to manage seed performance potential and subsequent yield, including improving seed quality and nutrient delivery.

ELECTROCHEMICAL BEHAVIOR OF CADMIUM BY ALTERNATING CURRENT POLARIZATION IN HYDROCLORIC ACID SOLUTION

Aisaule Sydykova — 2024-03-31

Abstract. Introduction. This paper presents the results of a study of the electrochemical behavior of a cadmium electrode in aqueous solutions of hydrochloric acid under polarization by stationary and non-stationary currents and shows the possibility of synthesis of its chloride. The purpose is to develop the electrochemical behavior of cadmium under alternating current polarization in a solution of perchloric acid. Methods. During the study, it was found that when two cadmium electrodes are polarized with an alternating current of 50 Hz, their dissolution does not occur, however, when one electrode is replaced with a titanium one, cadmium is intensively dissolved. Results and discussion. The influence of the main parameters, such as the duration of electrolysis, current density, concentration and nature of the electrolyte on the electrochemical process has been studied. A schematic diagram of an installation for dissolving cadmium by polarization with a non-stationary current is proposed. It is shown that on the titanium electrode in the range of 20-80 kA/m², the current yield of the dissolution of the cadmium electrode gradually increases, and with a current density equal to 80 kA/m², the current yield reaches 135%. Conclusion. It is shown that with alternating current polarization, the rate of chemical dissolution of cadmium, increases with the release of hydrogen. During the experiment, with the polarization of the cadmium electrode by alternating current, the possibility of obtaining cadmium chloride was shown. Based on chemical and X-ray phase analyses, it was proved that cadmium forms compounds CdCl₂∙H₂O.

AN ELECTROCHEMICAL METHOD FOR THE REGENERATION OF TRIVALENT IRON TO INCREASE THE EFFICIENCY OF IN-SITU LEACHING OF URANIUM

Makpal Turlybekova — 2024-03-31

Abstract. Introduction. Due to the increasing demand for electricity with the development of production and general infrastructure, increasing the production of uranium as an economically and environmentally efficient source of energy is an urgent problem. The purpose of this study is to develop an electrochemical method for the regeneration of iron (III) ions used as a uranium oxidizer in the process of in-situ leaching of uranium minerals with sulfuric acid solutions. Methods. The mechanism of reactions in the iron (II)-iron (III) redox system was studied by recording potentiodynamic polarization curves and conducting electrolysis of the oxidation of divalent iron ions under galvanostatic conditions. Results and discussion. Cathode-anodic and anodic-cathode cyclic polarization curves taken on platinum electrodes showed that the redox reactions of iron ions are reversible and these reactions occur at a slight overvoltage. The influence of the main electrochemical parameters (current density, concentrations of iron (II) ions and sulfuric acid) on the oxidation of divalent iron ions was studied for the first time using granular anode electrodes, the electrode spaces of which are separated by an anionite membrane. It has been found that the use of granular graphite electrodes in the oxidation divalent iron ions increases the current output by more than 2 times compared to a plate graphite electrode. Conclusion. According to the results of the study, it was noted that under optimal conditions, the current output of the oxidation of divalent iron ions exceeds 90%. Extensive research has shown that trivalent iron ions, widely used in the in-situ leaching process for uranium production, can be regenerated by electrochemical methods.

SYNTHESIS OF QUATERNARY AMMONIUM SALTS ISONICOTINIC AND NICOTINIC HYDRAZONES ACIDS AND THEIR ANTI-INFLAMMATORY ACTIVITY

Serik Fazylov — 2024-03-31

Abstract: Introduction. Currently, the number of infections caused by strains of bacteria that are not sensitive to antibiotics and antiseptics is growing worldwide. A similar increase in bacterial resistance is observed for both nosocomial infections and community-acquired human-to-human infections. An important task for chemists and pharmacologists is the synthesis of new compounds and the establishment of a structure-bioactivity relationship. The purpose of this work is to study the effect of the structure of quaternary ammonium derivatives of hydrazones of isonicotinic and nicotinic acids on the manifestation of their anti-inflammatory properties. Results and discussion. The alkylation of nicotinic acid hydrazones produced their new quaternary ammonium salts (43.7-70.7%). The methodology for the synthesis of quaternary ammonium compounds of hydrazones included obtaining a variety of structures by introducing one or two fluorine and bromine-containing fragments into their structure. The structure of compounds was confirmed by ¹H, ¹³C NMR spectroscopy. Conclusion. New quaternary ammonium salts of nicotinic acid hydrazones have been obtained. The study of anti-inflammatory activity was carried out using the method of formalin paw edema in rats. The acute inflammatory reaction was reproduced by subplantar administration of 2% formalin solution. Compared with ibuprofen at a dosage of 100 mg/kg, these compounds were ineffective (p₂<0.05). According to the results of the analysis of possible pharmacological effects, it was also revealed that new compounds may have an effect on the regulation and production of ketone bodies, the enzymatic activity of transaminases. New alkylated hydrazones of isonicotinic and nicotinic acids may be of interest for studying their antituberculous and antiviral activities.