Human calcitonin. V. Synthesis and characterization of the protected calcitonin M-(1-10)-decapeptide

The present report describes in detail the synthesis and characterisation of the protected Calcitonin M decapeptide 1–10, , a key intermediate in the synthesis of Calcitonin M. I. was obtained from the openchain precursor Boc-Cys (Trt)-Gly-Asn-Leu-Ser (But)-Thr (But)-Cys (Trt)-Met-Leu-Gly-OH (II) by oxidation with iodine in a yield of 70%, after purification by counter-current distribution. II was prepared by fragment coupling of the sequences 1–4 and 5–10. The free calcitonin M (1–10)-decapeptide, obtained from I by removal of the protecting groups by acidolysis, has no hypocalcaemic activity and does not inhibit specific binding of calcitonin M to its antibodies in rabbit serum.     

Human calcitonin. Structure of calcitonin M and D

Human calcitonin M and its dimer calcitonin D, two highly active peptides isolated from C cell tumours, were subjected to sequence studies using chemical and enzymatic methods. For calcitonin M, containing 32 amino acid residues, the following structure was derived: Though the disulphide bridge between position 1 and 7, and the C-terminal proline amide of human calcitonin M are the same as in porcine α-thyrocalcitonin, many amino acid residues - 18 in all - are different throughout the molecule. Arginine and tryptophan are absent; on the other hand, lysine and isoleucine are to be found at position 18 and 27 respectively. Methionine changes its place from position 25 to 8 adjacent to the disulphide bridge. Experimental evidence indicates that calcitonin D represents the antiparallel dimeer of calcitonin M.     

Human calcitonin. IV. Synthesis of calcitonin M

A preliminary account is giver of the synthesis of calcitonin M (I), isolated from human C-cell tumour tissue [2] [3]. Identity of the synthetic and the natural hormone was established by thin-layer chromatography, thin-layer electrophoresis and conversion to oxidation products, as well as by reference to the pattern of tryptic degradation and by comparing the biological activity of the two hormones. The findings also afforded additional confirmation of the results of structural elucidation [1]. In the synthesis of I, use was made of methods described previously [4] for the preparation of porcine α-thyrocalcitonin, and also of a new method [5] which easily permits the formation of cyclic cystine peptides.     

Allium carbohydrates I. Isolation and characterization of the polysaccharides

Summary 1. The amounts of glucofructans in 15 species of plants of the genusAllium L. growing in Central Asia have been studied.2. The polydispersity of all the glucofructans isolated has been established. Fractionation of the glucofructan fromA. sativum L. yielded homogeneous fractions with mol. wt. 1900 and 5000. On the basis of their IR spectra and the results of periodate oxidation, they have been assigned to the glucofructans of the inulin type.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 2, pp. 137–142, March–April, 1979.     

Oxasilacyclopropane. Isolation and characterization

A crystalline oxasilacyclopropane was isolatedby the reaction of photochemically induced dimesitylsilylene with 1,1,3,3-tetramethyl-2-indanone, and the exact structure of the oxasilacyclopropane was confirmed by X-ray crystal analysis.     

Polysaccharides ofPolygonatum I. Isolation and characterization of polysaccharides fromPolygonatum sewerzowii

Summary The water-soluble polysaccharides of the rhizomes of thePolygonatum sewerzowii Regl. have been studied. A method has been developed for separating the polysaccharide fraction. A new native acetylated glucomannan has been isolated which has been called severan and consists of manno- and glucopyranose residues linked with one another by -1 4 bonds in a ratio of 15.4:1.Institute of the Chemistry of Plant Substances, Academy of Plant Substances of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 555–559, September–October, 1978.     

Asparagus polysaccharides. I. Isolation and characterization of polysaccharides ofA. neglectus: Glucomannans of the roots

Water-soluble polysaccharides and pectin substances have been isolated from various organs ofA. neglectus and their quantitative amounts and monosacchardie compositions have been determined. Native acetylated glucomannans (A, B, and C) containing 13, 15, and 20% of acetyl groups and being homogeneous according to the results of gel chromatography have been isolated from the roots. On the basis of the results of periodate oxidation, methylation, and IR spectroscopy it has been established that the neutral polysaccharides of the roots ofA. neglectus is a mixture of three glucomannans consisting of β-1→4 linear-bound D-gluco- and D-mannopyranose residues.     

Curamycin—I Isolation and characterization of some hydrolysis products

From cultures of Streptomyces cura-coi, a chlorine containing glycosidic antibiotic, named curamycin, has been isolated. Curamycin on acid hydrolysis yields a crystalline product, curacin, and a mixture of monosaccharides. Curacin, which contains all of the chlorine of curamycin, is the ester of dichloroisoeverninic acid (3,5-dichloro-4-hydroxy-6-methoxy-2-methyl-benzoic acid) with a di-desoxyaldose C₆H₁₂O₄, whose structure has not as yet been established. Three other monosaccharides are present, two of which could be identified as -lyxose and 4-O-methyl- -fucose.     

Asparagus polysaccharides. I. Isolation and characterization of polysaccharides ofA. neglectus: Glucomannans of the roots

Water-soluble polysaccharides and pectin substances have been isolated from various organs ofA. neglectus and their quantitative amounts and monosacchardie compositions have been determined. Native acetylated glucomannans (A, B, and C) containing 13, 15, and 20% of acetyl groups and being homogeneous according to the results of gel chromatography have been isolated from the roots. On the basis of the results of periodate oxidation, methylation, and IR spectroscopy it has been established that the neutral polysaccharides of the roots ofA. neglectus is a mixture of three glucomannans consisting of -14 linear-bound D-gluco- and D-mannopyranose residues.Deceased.Institute of the Chemistry of Plant Substances, Academy of Sciences of the Uzbek SSR, Tashkent. Translated from Khimiya Prirodnykh Soedinenii, No. 6, pp. 702–706, November–December, 1981.     

Polyether azomethines. I. Synthesis and characterization

Six new polyether azomethines were synthesized by melt and solution polycondensation of six different diamines with 4,4′-[1,4-phenylene bis(oxy)] bisbenzaldehyde. The polymers synthesized by solution method are yellow to white in color and had inherent viscosities up to 0.59 dL/g in concentrated H₂SO₄. The polymers obtained by melt condensation show higher viscosity. Except polymer IV , others are insoluble in common organic solvents. The polymers were characterized by IR, x-ray, elemental analysis, and DSC study. The thermal stability of the polymers was evaluated by TGA and IGA study. Polymers I-III are highly thermally and thermooxidatively stable and exhibit no appreciable decomposition up to 420°C both in air and nitrogen atmosphere. It was shown that the curing of the polyazo-methines takes place by opening up of the ? CH?N? linkages at higher temperature. The electrical conductivities of the virgin and iodine doped polymers were as high as 10^?11?10^?16 and 10^?6?10^?8S cm^?1, respectively, at 30°C. Electronic spectra of the undoped polymers ( I-III ) indicated a large bathochromic shift of the ? – ?^* absorptions band (376 nm) due to ? C?N? bonds of the model compound. This can be attributed to extensive delocalization of the electrons along the polymer chain. © 1995 John Wiley & Sons, Inc.     

Polyurethane-polyacrylamide IPNs. I. Synthesis and characterization

Hydrophobic-hydrophilic interpenetrating polymer networks (IPNs) of polyurethane and polyacrylamide have been synthesized. The IPNs have been characterized by IR, thermal, and mechanical studies. SEM studies indicate phase mixing of some IPNs. Solvent resistance and surface hydrophilicity as evidenced by contact angle measurements suggest that these IPNs could be used for biomedical applications.     

Cyclolinear polysiloxanes. I. Synthesis and characterization

The synthesis and characterization of two novel cyclic siloxanes, diacetoxydiethyltetramethylcyclotetrasiloxane and diacetoxytriethylpentamethylcyclopentasiloxane, and cyclolinear polymers synthesized from these monomers are presented. The cyclic siloxanes were synthesized from tetramethylcyclotetrasiloxane and pentamethylcyclopentasiloxane, respectively, by acetylation followed by ethylation. The cyclic monomers were characterized with ¹H NMR spectroscopy. Subsequently, the cyclic siloxanes were self‐condensed into cyclolinear polysiloxanes and cocondensed (extended) with silanol‐terminated polydimethylsiloxane into high‐molecular‐weight polymers containing cyclic units withlinearpolydimethylsiloxane spacers (extended cyclolinear polysiloxanes). The molecular weights of both the cyclolinear polysiloxanes and extended cyclolinear polysiloxanes were determined. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4039?4052, 2006     

Isolation and characterization of thermophilic benzothiophene-degrading Mycobacterium sp.

A bacterial strain, SWU-4, capable of using benzothiophene (BT) as a sole carbon and energy source was isolated from a petroleum-contaminated site in Thailand and identified by 16S rRNA gene sequence analysis to be in the genus of Mycobacterium. The strain was Gram-positive, nonspore former, and grew at 50° C. Colonies of the strain on nutrient agar were rod-shaped, smooth with a convex surface, slightly mucoid, and yellow pigmented. The thermophilic Mycobacterium sp. strain SWU-4 rapidly degraded 2% (w/v) BT at 50°C. Interestingly, this strain was able to degrade a wide variety of organosulfur compounds including thiophene, bromo(α)thiophene, and 3-methylthiophene in liquid minimum medium at 50°C, which will be beneficial for industrial applications.     

Human sex hormone binding globulin (SHBG): Isolation, characterization and determination

Conclusions SHBG was highly purified by a 4-step method. Molecular weight, isoelectric point and DHT-binding were determined. Antibodies were generated and the well known transferrin crossreactivity was eliminated by affinity chromatography. SHBG as standard was not suitable for the RIA because of insufficient stability and was replaced by pregnancy serum. The tracer had to be chromatographed before each use. SHBG levels measured with this RIA are in the same range as has been reported in literature.

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Isolierung, Charakterisierung und Bestimmung von menschlichem sexualhormonbindendem Globulin

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Supported by the Deutsche Forschungsgemeinschaft (Mu 585/1-1)     

Nonionic reactive surfactants. I. Synthesis and characterization

A procedure to prepare nonionic reactive surfactants with different polymerizable groups is described. The synthesis involves the initiation of living anionic ring-opening polymerization of ethylene oxide and propylene oxide (for the hydrophilic part and the hydrophobic part, respectively) by a potassium salt prepared from the stoichiometric reaction of potassium hydride and diethylene glycol monomethyl ether. The resulting anion is reacted with chloride compounds (methacryloyl, allyl, vinylacetoyl) and maleic anhydride, as well as with isobutanoyl chloride, leading to a nonpolymerizable compound having a similar structure. Then, it was possible to produce a range of reactive surfactants more or less reactive with the monomers. These surfactants are expected to be used further in emulsion polymerization processes (styrene and butyl acrylate). This procedure gives good control of both hydrophobic and hydrophilic parts, and the end reaction for the different functionality of surfmers is quite quantitative. All the surfactants were characterized by size-exclusion chromatography and ¹H NMR. Physicochemical properties, such as the critical micellar concentration and the specific area, were also measured.     

Calcia-supported lanthanide oxides. I. Preparation and characterization

Ln₂O₃-CaO systems, where Ln=La, Sm, have been prepared by impregnation of calcia with aqueous solutions of Ln nitrates or by mixing both oxides. Decomposition at 1073 K leads to a slight decrease in the specific surface area when starting from Ln₂O₃, but to a sharp decrease when starting from the nitrates.