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Reduction of the alkaloid norfluorocurarine, which may adopt a zwitterionic form in basic medium but reverts to the initial state in acidic and neutral media according to UV and IR spectroscopy and an X-ray structure analysis, was studied. Alkaloids of the α-methyleneindoline type formed indolenine species in acidic and neutral media; indole derivatives, in basic medium.

Acyl- and alkyl-derivatives at the N1 and N4 atoms, respectively, of the indoline alkaloids copsinine (1) and pseudocopsinine (2), which were isolated from the plant Vinca erecta, were synthesized. Alkaloids 1 and 2 reacted with alkyl halides to give N4 substitution; with acetic anhydride, N1. In turn, N1-acyl-1 and -2 reacted with alkyl halides to bond the alkyl radical to the N4 position. Reaction products were identified using IR spectroscopy and HPLC-MS. Their structures were elucidated by X-ray crystal structure analyses (XSAs). The tetrahedral hybridization of N1 in the indoline alkaloids was favorable for forming their N1-acetyl derivatives, which is improbable in indole and α-methyleneindoline alkaloids.

X-ray crystal structure analyses (XSAs) were performed for the alkaloid (±)-vincadifformine (racemate) isolated from Vinca minor and (–)-vincadifformine methyliodide and the natural 5-oxo derivatives of (–)-vincadifformine ervinidinine and ervincinine isolated from Vinca erecta. The XSA results showed that tetrahedral N4 inverted on going from the base to the salt form of vincadifformine. The calculated heats of formation of the alkaloid in the two states indicated that these inverted forms were similar with a low (6 kcal/mol) barrier to inversion. The unshared electron pair of N4 was conjugated to the π-electrons of the neighboring ketone and N4 adopted trigonal-planar coordination in the 5-oxoderivatives ervinidinine and ervincinine. Conjugation of the unshared electron pairs on N1 and N4 was one of the main reasons for the alkaloids forming salts under ordinary conditions.

The X-ray diffraction study of an indoline alkaloid, pseudokopsinine, extracted from the plant Vinca erecta and its mono- and double salts is performed. The experimentally determined positions of Н atoms suggest the sp 3 hybridization of the indoline nitrogen atom in the base and salts. The pseudokopsinine base and double salt have an intramolecular Н bond between the NH group proton and the ether oxygen atom of the methoxycarbonyl group, which is absent in the monosalt and the related indolines. The intermolecular Н bonds and/or the packing efficiency cause a conformational change in F and Е heterocycles in the indoline hetero framework of pseudokopsinine salts in comparison with that observed in the base.

Indoline alkaloids kopsinilam and kopsinine extracted from the plant Vinca erecta have been studied by X-ray crystallography; mono and double salts of the latter alkaloid also have been examined. Experimentally determined positions of Н atoms suggest sp 3 hybridization of the indoline nitrogen atom N1 in the bases and the salts. Tetrahedral hybridization of the atom N1 in indoline alkaloids favors the formation of their double salts, what is unlikely for indole and indolinine alkaloids. In the halogen double salts there is an intramolecular Н bond between one of the protons of the NH2 group and the oxygen of the methoxycarbonyl group, that is absent in the mono salts and pure bases.

The crystal structures of 12-hydroxynorfluorocurarine (vincanidine) isolated from the plant Vinca erecta, its hydrochloride monohydrate, quaternary salts — chloromethylate and iodomethylate, and the quaternary base (zwitterionic betaine) have been studied. The asymmetric centers of the molecules have the 3S, 7R, 15S configuration. In all cases, the carbonyl group is in a twisted orientation with respect to the N1H group and participates in the intramolecular H-bond with this group. In crystals, the 12-hydroxy group is involved in intermolecular interactions. The quaternary base of 12-hydroxynorfluorocurarine contains a zwitterionic form of the alkaloid due to deprotonation of the 12-hydroxyl group. The packing in the crystal structure of 12-hydroxynorfluorocurarine and the quaternary base contains voids (19.8 % and 21.8 % of the total volume of the crystal cell, respectively) of the channel type along the c crystallographic axis.

The inhibitory activities of the new gossypol-free cotton variety Bukhara-9 and varieties UzFA-705 and Mirishkor were compared. It was found that Bukhara-9 and UzFA-705 had the same inhibitory activity as the resistant regionalized variety An-Bayaut-2. The inhibitory activity of Mirishkor was greater than that of variety Turon, which was developed for growing in arid zones. It was shown that Mirishkor proteinase inhibitors suppressed practically fully growth in vitro of the phytopathogenic fungus Fusarium oxysporum.

The crystal and molecular structures of quaternary salts and the quaternary base of 12-methoxynorfluorocurarine (vincanicine) that was isolated from the plant Vinca erecta were studied. The molecular structure, i.e., conformation, ring fusion, and absolute configuration (3S,7R,15S) of asymmetric centers, did not differ from that of norfluorocurarine. The carbonyl (C17=O) and N1H groups in the quaternary salts and base were mutually twisted and were involved in the crystal only in intermolecular H-bonds. The enol form in the zwitterionic alkaloid that existed in alkaline medium was observed in the crystal of 12-methoxynorfluorocurarine quaternary base.

Reduction of norfluorocurarine by sodium in EtOH formed deoxytetrahydronorfluorocurarine and tetrahydronorfluorocurarine. The latter was identical to the Wieland–Humlich 18-deoxyglycol. Reduction of norfluorocurarine by sodium borohydride in alkaline solution occurred with opening of rings C and E and formation of the new indole base 16-decarbmethoxyepistemmadenine. Reduction of fluorocurarine chloride or iodide by sodium borohydride formed the corresponding de-acetylretuline salts. The structures of the products were established by x-ray crystal structure analyses. Norfluorocurarine and representatives of the α-methylenindolenine series formed indoline derivatives upon reduction in acidic and neutral solutions; indole derivatives, in alkaline solution.

The indole alkaloid norfluorocurarine was reacted with phenylhydrazine. An x-ray crystal structure analysis found that the phenylhydrazine was bonded through its N atoms to C2 and C17 and that the N1–C2 bond of the indole core was cleaved to form an NH2 group and a water molecule was released.

Single crystal XRD is used to study the crystals of salts of indole alkaloid norfluorocurarine: hydrochloride recrystallized from absolute alcohol, dihydrate hydrochloride recrystallized from water, methochloride monohydrate recrystallized from water, solvate form of methochloride obtained from ethanol, and methobromide monohydrate. Intra- and intermolecular hydrogen bonds are analyzed in these crystals. The crystal structures of norfluorocurarine methochloride and methobromide monohydrates are isomorphic. In norfluorocurarine salts, the orientation of the carbonyl group is determined by the intramolecular C19=O…H-N1 hydrogen bond that is absent in the solvate form with ethanol.

Structures of the alkaloids (−)-norfluorocurarine, its racemate (±)-norfluorocurarine from Vinca erecta, and fluorocurarine obtained by N(β)-methylation of (−)-norfluorocurarine were established by x-ray crystal structure analyses. The alkaloid crystallized with two molecules in the asymmetric unit for the first two crystals. The asymmetric unit of (±)-norfluorocurarine crystal consisted of two antipods. The asymmetric unit in the crystal of the last compound consisted of the N(β)-methylated cation and a hydroxide anion. The formation of bimolecular associates through intermolecular N–H…O H-bonds was typical of these crystal- line structures. An associate in the crystal structure of fluorocurarine involved two hydroxide anions.

The bisindole compound 2β,16α,2′β,16′β(H)-tetrahydronordihydrotoxiferine consisting of two diastereoisomeric deoxytetrahydronorfluorocurarine moieties was isolated from the reduction mixture of the alkaloid norfluorocurarine. 16-Deformyl-2,16,17,20-tetrahydro-20,21-dehydronorfluorocurarine was produced by dehydrogenation of norfluorocurarine; N(β)-methyldihydrodefluorocurarine, by hydrogenation of fluorocurarine. The structures of the synthesized compounds were established by x-ray structure analyses. The configurations of the asymmetric centers in 2β,16α,2′β,16′β(H)-tetrahydronordihydrotoxiferine were determined as 2S,3S,7R,15S,16R,2′S,3′S,7′R,15′S,16′S. Inversion to the R-configuration at the C15 center was observed in N(β)-methyldihydrodefluorocurarine whereas the configurations 3S and 7R were retained. Atom C2 adopted the S-configuration in 16-deformyl-2,16,17,20-tetrahydro-20,21-dehydronorfluorocurarine.

The alkaloid norfluorocurarine was reduced under various conditions to produce the novel bisindoline derivative 2,16-dihydro-19-oxo-C-dihydrotoxiferine and the previously known natural derivatives deoxydihydro-, deoxytetrahydro-, and tetrahydronorfluorocurarine. The structures of the synthesized compounds were identified using IR and UV spectroscopy; of newly produced 2,16-dihydro-19-oxoC-dihydrotoxiferine and deoxydihydronorfluorocurarine, also by x-ray structure analysis. Determination of the absolute configuration of N(α)-methylfluorocurarine chloride dihydrate by x-ray methods enabled the configuration of the 3S,7R,15S asymmetric centers in norfluorocurarine and 2S,3S,7R,15S in deoxydihydronorfluorocurarine to be determined. Also, the absolute configuration of 2,16-dihydro-19-oxoC-dihydrotoxiferine was determined as 2S,3S,7R,15R,16R in one part of the bisindoline and 3'S,7'R,15'S in the other.

The glutelin fraction was used as the food value index of local corn. The base-soluble fraction was used as a test of the glassiness of local strains of rice grain. The content of gliadins and glutelins did not change over 24 h after wheat grain cultivated in Uzbekistan was moistened.

Data on the proteinase complex from Carica papaya latex were reviewed. The properties and applications of the domestic preparation cucumazyme and known medicinal preparations based on papaya proteinases (caripazyme, lecozyme, lecopain) were compared.

Wheat grain cultivated in Uzbekistan had an increased content of water-soluble proteinaceous and relatively low gliadin and glutelin fractions. The amino-acid content in the studied varieties depended on the amount of protein in the grain.

Tryptic hydrolysates of cyanogen bromide fragments B-1, B-2, and B-3 have been studied. As a results, 23 tryptic peptides have been isolated and characterized and the primary structures of 22 of them have been established.

The processes involved in the hydrolysis of the proteins of the toxic seed meals of the castor-oil plant and the cotton plant with hydrochloric acid have been studied. The optimum conditions of hydrolysis, at which the yield of desired product amounts to about 40%, have been established. The use of activated carbon and the cation-exchange resin KU-2×8 have enabled a hydrolysate containing 80–85% of amino acids to be obtained.

A thionin-like protein with M. M. 5kDa has been isolated fromCrambe kotschyana seeds. It has been shown that crambin possesses, a low lytic action on erythrocytes but inhibits the Ca-ATPase of the sarcoplasmic reticulum of rabbit skeletal muscles. A disordering action of crambin on the structures of both the sarcoplasmic reticulum and liposomes has been established by ESR and microcalorimetry.

The N-terminal amino acids and the amino acid compositions of four species-specific proteins of two species of the cotton plant —Gossypium hirsutum andG. barbadense — have been determined. Peptide maps of tryptic hydrolysates of these proteins have been obtained and compared. Individual tryptic peptides have been isolated and purified. The N-ends, amino acid compositions, and amino acid sequences of individual peptides have been determined. The N-terminal sections of the proteins ofG. hirsutum andG. barbadense as far as the 16th amino acid residue have been sequenced. A comparative analysis has been made of the peptides and proteins of these cottonplant species.

The literature on proteinase inhibitors of plant origin over the last 15 years is discussed. The results of investigations are permitting an expansion of our ideas on the regulatory and protective functions of proteinase inhibitors, which play a primary role in the resistance of plants to phytopathogens and can be used as a test in selection practice.

It has been shown that dormant cotton seeds contain proteins capable of inhibiting the activity of the proteolytic enzymes of the pathogenVerticillium dahliae Kleb. An immunochemical method of evaluating the resistance of a cotton plant to this fungus has been developed.

A scheme has been developed for the isolation of an inhibitor of cottonseed protease A using affinity chromatography on protease-A—Sepharose 4B followed by gel filtration on Sephadex G-150. The molecular mass of the inhibitor is 20 kDa. The protein molecule consists of two subunits with different molecular masses.

A scheme has been developed to isolate and purify proteinase D from 3-day germinated cotton seeds. The physicochemical properties and substrate specificity were studied. It is found that cysteinic proteinase D cleaves auxiliary proteins to low-molecular-weight peptides and free amino acids.

An enzymatic-chemical method of isolating the complex of lipids, gossypol pigments, and water-soluble proteins from cotton seeds and meal has been developed which permits: a) the achievement of the maximum yield of all types of lipids without their degradation; b) a rise in the qualitative and food value of the oil and protein products isolated from the seeds, with an increase in the solubility of the latter; c) the extraction from cotton seeds of more than 75% and from cottonseed meal of 42% of the free gossypol. The method, in combination with Folch's procedure, is suitable for the quantiative estimation of the lipids, strongly bound to the protein of the nucleus.

Protease inhibitors of protein nature have been isolated from dormant cotton seeds. The participation of protease inhibitors in the mechanism of protecting the plant from wilt damage is discussed.

The proteins of the buffer-soluble fraction of the seeds of cotton plants of the speciesGossypium hirsutum, wild and ruderal varieties, have been investigated by electrophoresis in polyacrylamide gel and have been subdivided into two classes. Characteristic components have been detected in the protein spectra of these samples. In diploid species of the cotton plant, in addition to characteristic protein components, individual components are also observed.

A method has been developed for the quantitative estimation of ricinine in extracts and meal from two castor-oil plant seed tosters.

The results are given of the isolation and study of the proteinase complex from the milky juice of papaya grown under hothouse conditions in the Republic of Uzbekistan. It has been shown that the component composition, proteolytic activity, and pH optimum of the action of the complex obtained are similar to those of the complex proteinase preparation from the milky juice of papaya cultivated in the Black Sea littoral of the Caucasus.

A sorbent highly specific forVerticillium proteins has been obtained from BrCN-Sepharose and rabbit immunoglobulins. By affinity chromatography using this sorbent a protein immunologically similar to the proteins of the mycelium of the fungusV. dahliae has been isolated from cotton seeds of the Tashkent-1 variety. The molecular mass of the protein has been determined, and its proteolytic activity has been established.

The hydrolysis of the 11S globulin begins in the early stages of the germination of cotton seeds and is complete during the first 4–5 days. During the first 3 days, only limited hydrolysis of the reserve protein takes place, and only on the 4th day does it undergo far-reaching hydrolysis, after which the protein cannot be detected either by immunochemical methods or by electrophoresis and analytical ultracentrifugation.

Naringenin 7-O-(6″-O-p-coumaroly-β-D-glucopyranoside) and the new flavanone naringenin 7-O-(2″-O-p-coumaroyl-β-D-glucopyranoside) have been isolated from the seeds of Ricinus communis L. The structures of the compounds isolated were established on the basis of the results of chemical transformations and spectral characteristics.

It has been established by double immunodiffusion in agar that protease A (a proteolytic enzyme from dormant cotton seeds hydrolyzing the native reserve proteins) is present for the first 3–4 days during the germination of the seeds. An immunological affinity between trypsin and protease A has been revealed which indicates the presence of common structural elements in them.

The air-dry comminuted tomato stems were extracted with a mixture of chloroform and methanol. The yield of extractive substances was 8.2% of the weight of the stems, and the amount of unsaponifiable substances in the extract was 19.0%, that of carotenoids 1.2%, and that of chlorophylls 1.8% of the weight of the lipids. Among the lipids, we identified neutral and polar classes. In the neutral lipids we detected [by TLC on silica gel L 5/40 and Silufol in the hexane-diethyl ether (7:3, 6:4, and 6:6) systems with revelation by H2SO4, c~,c~'-bipyridyl, and iodine] hydrocarbons, carotenoids [UV spectrum (~'max, hexane, nm): 425,449, 478], esters of sterols and triterpenols with fatty acids, aliphatic alcohols, tocopherols, free fatty acids, triterpenols, sterols, and chlorophylls and their derivatives [UV spectrum (~'max, hexane, nm): 410, 432, 581, 610, 668]. Phospholipids present [TLC on silica gel in the chloroform-methanol-ammonia (65:35:5) system; spots revealed with the Dragendorffand Vas'kovskii reagents and ninlaydrin] were phosphatidylethanolamine, phosphatidylcholine, phosphatidylinositol, lysophosphatidylcholine, and phosphatidic acid, with phosphatidylcholine predominating. Among glycolipids we detected [by TLC in a system similar to that for the phospholipids, the spots being revealed with c~-naphthol] steryl glycosides and their esters with fatty acids, sulfoquinovosyldiacylglycerols, and mono- and digalaetosyldiacylglycerols, with the monogalactosyldiacylglycerols predominating. The total fatty acids were isolated by hot saponification with a 10% methanolic solution of KOH, as described in [2]. The fatty acids, in the form of their methyl esters, were analyzed by GLC on a Chrom-4 chromatograph. Composition of the fatty acids according to GLC (% on the weight of the acids): 10:0 (tr.); 12:0 (0.5); 14:0 (0.9); 15:0

Ricinine was isolated from the defatted flour of the seeds or meal with 85% aqueous ethanol. The extract was concentrated and was made alkaline with ammonia solution, and was reextracted repeatedly with chloroform. The completeness of extraction was monitored by the TLC method on Silufol in the UV at 254 nm. The chloroform extract was distilled to dryness, and the residue was crystallized from ethanol.

The amino-acid sequences of the chymotryptic peptides of the 7S globulin of cotton seeds have been determined.

It has been established by a polarographic analysis of the globulins of cotton seeds that the 7S and 11S golublins possess a two-step polarographic wave with a half-wave potential of −1.42 V. On the basis of the results of a study of the kinetics of thermal denaturation the high lability of the 11S globulin on heating has been shown. The conditions have been determined of the complete denaturation of the 11S globulin in 8 M urea solution and it has been established that the latter is an irreversible process.

Pronase hydrolysates have been obtained from cottonseed meal which were then used as a substrate for the performance of the plastein reaction. The possibility has been shown of introducing deficient amino acids — lysine methionine, threonine, and tryptophan — by means of this reaction.

The 11S-globulin has a complex stable quaternary structure in the formation of which three types of subunits participate. The aim of the work was to determine what forces form and stabilize the quaternary structure of this protein. The products of the maleylation and acetylation of the 11S-globulin and also the stability of the native 11S-globulin in the presence of ionic and nonionic detergents were investigated by disk electrophoresis. It was shown that hydrophobic interactions play a deciding role in the formation and stabilization of the quaternary structure of the 11S-globulin.