Synthesis and biological properties of a tryptophan-containing fragment of a myelin protein and its analogs

1. By the azide condensation of fragments followed by the hydrogenolysis of the completely protected nonapeptides formed, the encephalitogenic nonapeptides with the structure Phe-Ser-Try-Gly-Ala-Glu-Gly-Gln-Arc and two of its analogs — the 6-glycine and 5,6-diglycine compounds, have been synthesized. 2. It has been shown that the 6-glycine analog induces EAE, i.e., the side chain in position 6 is not essential for the appearance of EAE activity.     

Synthesis and physicochemical and encephalitogenic properties of analogs of a tryptophan-containing fragment of myelin protein

Summary 1. Analogs of the encephalitogenic nonapeptide with the substitution of glycine in the first and in the first and second positions and also with the deletion of the glutamic acid residue and the insertion of a glycine residue between the fifth and sixth positions have been synthesized.2. An investigation of the encephalitogenic activity of the compounds synthesized has shown the necessity for a hydrophobic N-terminal amino acid, since the replacement of phenylalanine by glycine leads to the inactivation of the compound. A change in the length of the encephalitogenic determinant also leads to the loss of EAE activity.3. The CD spectra of the peptides synthesized are identical in water, a 1% solution of SDS, and an 8 M solution of urea and do not change on heating to 50°C. It is obvious that under the conditions mentioned these compounds do not possess an ordered structure of the -helical type of a structure, and their dichroic absorption is due to the contribution of the aromatic side chains.Institute of Molecular Biology and Genetics, Academy of Sciences of the Ukrainian SSR, Kiev. A. V. Palladin Institute of Biochemistry, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 842–849, November–December, 1977.     

A study of the properties of synthetic analogs of the tryptophan-containing fragment 113–121 of the basic protein of myelin

New analogs of fragment 113–121 of the basic protein of myelin were synthesized: Phe-Ser-Trp-Gly-Ala-Glu-Gly-Gln-Arg, in which the phenylalanine in the first position has been replaced by L-alanine (V) and by D-phenylalanine (IX), and also a shortened analog with the deletion of the serine in the second position (XIII) and a lengthened analog with the insertion of glycine between the phenylalanine and tryptophan (XVII). In experiments on guinea pigs, one of the compounds obtained exhibited encephalitogenic activity. The circular dichroism spectra of compounds (I) and (IX), and also of some model compounds, have been studied in order to analyze the contribution of the aromatic amino acid residues to the dichroic absorption.

     

Synthesis and properties of styrenetricarbonylchromium and its analogs

The methods of synthesis and the reactivity of styrenetricarbonylchromium and its analogs as model objects for the study of the effect of the metal atom on the reactivity of the monomer -bond and the aromatic ring are described systematically and discussed. These compounds are unique initial substrates for the synthesis of metal-containing polymers and for the preparation of optical stereoisomers and materials for nonlinear optics.     

Synthesis and biological properties of novel structural analogs of isothiobarbamine

Russian Chemical Bulletin - Novel structural analogs of isothiobarbamine, which differ from the prototype scaffold by the substituent at position 2 of the pyrimidine heterocycle, were for the first...     

Synthesis and biological activity of RS-abscisic acid and its analogs

Summary RS-Abscisic acid and some of its analogs have been obtained. The biological activity of these compounds has been studied in dependence on their structure.It was found that precursors of RS-abscisic acid suppress the growth of segments of coleoptiles to a considerably smaller extent than the acid itself.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR. Timiryazev Institute of Plant Physiology. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 731–735, November–December, 1970.     

Synthesis and biological activity of RS-abscisic acid and its analogs

Chemistry of Natural Compounds - RS-Abscisic acid and some of its analogs have been obtained. The biological activity of these compounds has been studied in dependence on their structure. It was...     

Synthesis and biological activity of mycalolide analogs

Mycalolide analog 4, consisting only of the side chain of mycalolide B (2), a trisoxazole macrolide of marine origin, was stereoselectively synthesized using Roush crotylboration, an Evans aldol reaction, and a Paterson aldol reaction as key steps. The analog 4 was found to have strong actin-depolymerizing activity.     

Synthesis and biological evaluation of neopeltolide and analogs

The synthesis of neopeltolide analogues that contain variations in the oxazole-containing side chain and in the macrolide core are reported along with the GI(50) values for these compounds against MCF-7, HCT-116, and p53 knockout HCT-116 cell lines. Although biological activity is sensitive to changes in the macrocycle and the side chain, several analogues displayed GI(50) values of <25 nM. Neopeltolide and several of the more potent analogues were significantly less potent against p53 knockout cells, suggesting that p53 plays an auxiliary role in the activity of these compounds.     

Synthesis and properties of analogs of pyridoxal

A method for the synthesis of analogs of pyridoxal-2-norpyridoxal, 6-methyl-2, 4-pyridoxal, and 6-methylpyridoxal—has been worked out. The reaction of 5-ethoxyoxazoles with maleic diesters gave diesters of substituted 3-hydroxycinchomeric acids, which were converted by reduction with lithium aluminum hydride into analogs of pyridoxine. The latter were oxidized with magnesium dioxide to the corresponding analogs of pyridoxal. The oximes of the aldehydes and their Schiff's bases with p-phenetidine have been obtained. Analogs of pyridoxamine have been obtained by the hydrogenation of the oximes. The UV absorption spectra of the compounds and the ratios of the ionic forms in aqueous solutions have been studied.     

Synthesis and properties of analogs of pyridoxal

A method for the synthesis of analogs of pyridoxal-2-norpyridoxal, 6-methyl-2, 4-pyridoxal, and 6-methylpyridoxal—has been worked out. The reaction of 5-ethoxyoxazoles with maleic diesters gave diesters of substituted 3-hydroxycinchomeric acids, which were converted by reduction with lithium aluminum hydride into analogs of pyridoxine. The latter were oxidized with magnesium dioxide to the corresponding analogs of pyridoxal. The oximes of the aldehydes and their Schiff's bases with p-phenetidine have been obtained. Analogs of pyridoxamine have been obtained by the hydrogenation of the oximes. The UV absorption spectra of the compounds and the ratios of the ionic forms in aqueous solutions have been studied.     

Synthesis and biological evaluation of aziridine-containing analogs of phytosphingosine

Six new aziridine-containing analogs of phytosphingosine designed as constrained anhydrophytosphingosine were synthesized. The synthetic route developed also afforded an access to an original bicyclic analog of the natural anhydrophytosphingosine jaspine B. All these new compounds were evaluated for their capacities to affect melanoma cell viability.     

Synthesis and some properties of acrylic and methacrylic derivatives of chlorophos and its analogs

Conclusions The reaction of chlorophos and its analogs with the acid chlorides of the acrylic, methacrylic and-fluoroacrylic acids gave some new unsaturated compounds that possess fungicidal action.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 883–886, April, 1973.     

Structural analogs of tetrapyrrole macrocycles and their biological properties

The review summarizes data on the synthesis and properties of analogs of ABBB-and ABAB-type tetrapyrrole macrocycles and their metal complexes. The structural features of these compounds are discussed. Data on aromaticity and biological properties are considered. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 663–679, April, 2007.