101 results about "Substituted Amino Acid" patented technology

A D-aminotransferase can be modified so as to efficiently produce (2R, 4R)-monatin having high sweetness intensity from 4-(indol-3-ylmethyl)-4-hydroxy-2-oxoglutaric acid by substituting an amino acid at least at one of positions (positions 100, 180 to 183,243 and 244) involved in efficiently producing the (2R, 4R)-monatin in an amino acid sequence of a wild-type D-aminotransferase represented in SEQ ID NO:2.

Methods are described for treating an influenza viral infection or associated diseases, disorders or mechanisms in a subject, comprising administering to the subject a therapeutically effective amount of a catecholic butane of the general formula (I) or a pharmaceutically acceptable salt thereof:

wherein R₁ and R₂ each independently represents a hydrogen, a lower alkyl, a lower acyl, an alkylene, or —OR₁ and —OR₂ each independently represents an unsubstituted or substituted amino acid residue or pharmaceutically acceptable salt thereof; R₃, R₄, R₅, R₆, R₁₀, R₁₁, R₁₂ and R₁₃ each independently represents a hydrogen, or a lower alkyl; and R₇, R₈ and R₉ each independently represents a hydrogen, —OH, a lower alkoxy, a lower acyloxy, an unsubstituted or substituted amino acid residue or pharmaceutically acceptable salt thereof, or any two adjacent groups together may be an alkyene dioxy; with the proviso in certain circumstances that where one of R₇, R₈ and R₉ represents a hydrogen, then —OR₁, —OR₂ and the other two of R₇, R₈ and R₉ do not simultaneously represent —OH.

Provided are crystalline α, α-disubstituted amino acids and their crystalline salts containing a terminal alkene on one of their side chains, as well as optionally crystalline halogenated and deuterated analogs of the α, α-disubstituted amino acids and their salts; methods of making these, and methods of using these.

The invention discloses a preparation method of an organic-Se nutrient solution for crops. According to the method, bacillus subtilis is adopted to perform fermentation treatment on Se-enriched yeast, the Se-enriched yeast is hydrolyzed by the aid of protease produced in the metabolic process of the bacillus subtilis, a Se-enriched hydrolysate is obtained, and the organic-Se nutrient solution for the crops is prepared. The invention further discloses the organic-Se nutrient solution applied to the crops and produced with the preparation method of the organic-Se nutrient solution for the crops as well as an application of the organic-Se nutrient solution for the crops. With the adoption of the preparation method, all raw materials are sufficiently and reasonably utilized, complete and sufficient utilization of the raw materials is realized, no residues and residual liquids are produced, and environmental pollution is avoided; the content of organic-Se in the prepared organic-Se nutrient solution for the crops is high, the organic-Se exists in modes of Se substituted amino acid and short peptide, plant absorption is facilitated, and the content of the organic-Se in agricultural products can be remarkably increased.

The present invention relates to the methods of synthesizing hydrochloride salt of N-fatty acyl substituted amino acid ethyl ester which comprises a) condensation of aqueous solution of esterified amino acid with an acid halide to obtain an intermediate suspension and b) isolating a hydrochloride salt of N-fatty acylsubstituted amino acid ethyl ester from the intermediate suspension.

The present invention provides compositions and methods for the therapeutic and/or prophylactic treatment of pathogen infections and/or disease states. The compositions may comprise variable epitope libraries (VELs), containing antigenic epitopes with one or more amino acid substitutions in the native epitope sequence. In preferred embodiments, the substituted amino acid may be replaced with each of the 19 other naturally occurring amino acids. In more preferred embodiments, multiple amino acid residues may be substituted. Such compositions and methods may be of use for production of vaccines against pathogens or diseases that show a high degree of genetic variability.

The invention relates to a L-asparaginase variant with increased activity, and is a variant of escherichia coli wild type L-asparaginase shown in a SEQ ID NO:3, and the variant comprises an one or a plurality of amino acid substituted amino acid sequence on 48th site, 49th site, 152nd and 283rd by corresponding to a SEQ ID NO:3. The invention also provides the separated nucleic acid containing the nucleotide sequence which codes the L-asparaginase variant, a recombinant expression construct containing the nucleic acid and a recombinant host cell containing the expression construct. In addition, the invention also provides a method for generating the L-asparaginase variant. The invention also provides a pharmaceutical composition used for treating tumor containing the L-asparaginase variant.

The invention discloses a rare earth supermolecular metal gel based on a fluorene-substituted phenylalanine gelator, and belongs to the field of functional materials. In the invention, the fluorene-substituted phenylalanine is dissolved in organic solvent and is coordinated with rare earth ions, so that under the pi-pi interaction and hydrogen bond interaction of the fluorene-substituted amino acid, the rare earth supermolecular gel is self-assembled; the gel has the specific fluorescent characteristic of the rare earth and is high in luminescent intensity and fluorescent efficiency; the rareearth supermolecular gel has excellent heat resistance, and can hold the gel state and maintain the fluorescent intensity even at 30-100 DEG C. The fluorescent intensity has excellent reversible responsibility to acid and alkali and can be maintained even after multiple-time circulation. The preparation method of the rare earth supermolecular gel is simple and quick and is free of heating treatment, wherein the gelator is easy to obtain and biocompatibility is excellent. The invention extends the application of the rare earth supermolecular gel in the fields such as high-end anti-fake, sensors, and biomedical treatment, etc.

A method for the synthesis of daptomycin or a daptomycin analogue is carried out on a resin to form a linear precursor followed by a serine ligation macrocyclization in solution. Daptomycin analogues can differ from daptomycin by substitution of amino acids residues and/or deletion or addition of amino acid residues. Daptomycin analogues can include a different fatty acid in the side arm of the daptomycin analogue.

Amino acid functionalized polymers useful for graft copolymerization prepared by reacting a mixture containing, for chain transfer, a thio-substituted amino acid and an ethylenically unsaturated monomer.

The present invention provides a mutant of Thermobifida fusca cutinase and a preparation method thereof. The mutant includes one or two active center sites of cutinase corresponding to Thermobifida fusca The substitution of nearby amino acid residues, I218A, Q132A/T101A and W195A/F249A all improved the catalytic efficiency of cotton fiber, and the catalytic efficiency of mutant I218A to cutin was 50% higher than that of procutinase; The catalytic efficiency of fiber ethylene terephthalate (PET) is 3 times higher than that of procutinase, and these three mutants have broad application prospects in textile fiber pretreatment.

The present invention relates to a process for preparing hydrochloride salt of N-fatty acyl substituted amino acid ethyl ester. Said process includes the steps of: dissolving L-arginine ethyl ester dihydrochloride in distilled water with continuous agitation for a period of about 10 to about 20 minutes to obtain a clear solution; lowering the temperature of the clear solution to about 5° C. to about 10° C. to obtain a cooled solution; adjusting the pH of the cooled solution in the range of about 7 to about 8 by adding sodium hydroxide solution; adding at least one organic solvent to the clear solution with continuous agitation to obtain an intermediate mixture; condensing the intermediate mixture by simultaneously adding an acid halide and 20% sodium hydroxide solution at a temperature of about 7° C. to about 9° C. and at a pH in the range of about 7.2 to about 7.5 for about 2 hours to obtain a mixture; raising the temperature of the mixture to about 18 to about 20° C. followed by addition of sodium hydroxide to adjust the pH of the mixture to about 7.3; warming the mixture at a temperature of about 25 to about 30° C. to obtain a resultant mixture containing organic phase and aqueous phase; separating the organic phase and aqueous phase of the resultant mixture by settling the mixture; and distilling the organic phase under vacuum at a temperature of about 70° C. to about 75° C. to obtain a hydrochloride salt of ethyl lauroyl arginate.

This invention relates to novel compounds of Formula (I) for use as vascular damaging agents:

wherein: X is selected from: —O—, —S—, —S(O)—, —S(O₂)—, —N(R₄)— or —N(R₄)CH₂C(O)—; R₁ is independently selected from: amino, halo, hydroxy, —OPO₃H₂, C_1-4alkyl, C_1-4alkoxy, N-C_1-4alkylamino, N,N-di-C_1-4alkanoylamino or C_1-4alkylthio wherein the amino group is optionally substituted by an amino acid residue and the hydroxy group is optionally esterified; R₂ is selected from: hydrogen or C_1-4alkyl; R₃ is selected from: hydrogen or C_1-4alkyl; R₄ is selected from: hydrogen or C_1-4alkyl; n is 0, 1 or 2; and p is 0, 1, 2 or 3; or a salt, pro-drug or solvate thereof. The invention also relates to methods for preparing compounds of Formula (I), to their use as medicaments (including methods for the treatment of angiogenesis or disease states associated with angiogenesis) and to pharmaceutical compositions containing compounds of Formula (I).

Methods are described for treating an influenza viral infection or associated diseases, disorders or mechanisms in a subject, comprising administering to the subject a therapeutically effective amount of a catecholic butane of the general formula (I) or a pharmaceutically acceptable salt thereof: wherein R1 and R2 each independently represents a hydrogen, a lower alkyl, a lower acyl, an alkylene, or -OR1 and -OR2 each independently represents an unsubstituted or substituted amino acid residue or pharmaceutically acceptable salt thereof; R3, R4, R5, R6, R10, R11, R12 and R13 each independently represents a hydrogen, or a lower alkyl; and R7, R8 and R9 each independently represents a hydrogen, -OH, a lower alkoxy, a lower acyloxy, an unsubstituted or substituted amino acid residue or pharmaceutically acceptable salt thereof, or any two adjacent groups together may be an alkyene dioxy; with the proviso in certain circumstances that where one of R7, R8 and R9 represents a hydrogen, then -OR1, -OR2 and the other two of R7, R8 and R9 do not simultaneously represent -OH.

The invention discloses a synthesis method of a Beta-silicon group-substituted amino acid derivative. The synthesis method comprises the following steps: using amino acid of N-terminus amino group-protected and carboxy-terminus-introduced 8-aminoquinoline and hexamethyl disilane as raw materials; using hexamethyl disilane as a silicon group forming agent; using palladium acetate as a catalyst; using substituted quinone as an oxidant; using silver salt and acetate as additives; performing silicon group reaction in an organic solvent; performing column chromatography separation and purification to obtain the Beta-silicon group-substituted amino acid derivative. The synthesis method provided by the invention is mild in reaction condition, simple in process, convenient to operate and high in stereoselectivity.

The invention provides a leonurine derivative and application of the leonurine derivative in preparation of a medicine for preventing or treating ischemic cerebrovascular diseases. The leonurine derivative has a structure as shown in a general formula (I), wherein X is selected from O or NH; Y is selected from any one of natural amino acid, substituted amino acid or amino alcohol; Z is selected from H, proline and any substituted proline. Pharmacological experiments prove that the leonurine derivative provided by the invention has the effects of neuroprotection, cerebral infarction area reduction and animal neurobehavioral scoring, and is good in safety, so that the leonurine derivative has important significance for developing novel medicines for preventing or treating ischemic cerebrovascular diseases.

The invention discloses deoxypodophyllo and 5-fluorouracil spliced compounds, and a preparation method and application of the compounds. The structure of the deoxypodophyllo and 5-fluorouracil spliced compounds is shown as a formula I or II. The preparation method for the spliced compounds comprises the following steps of: mixing 4'-demethyl-4-deoxypodophyllo and 5-FUalkyl acyl-N-substituted amino acid or 5-FU substituted fatty acid, and reacting in the presence of a condensing agent of dicyclohexylcarbodiimide (DCC) and a catalyst of N,N-dimethyl-aminopyridine to obtain the target compounds shown as the formula. The deoxypodophyllo and 5-fluorouracil spliced compounds can be applied to preparing medicines for treating tumors.

The various embodiments herein provide a chimeric truncated and mutant variant of a tissue plasminogen activator (t-pa) and a method for preparing the same. According to an embodiment herein, the mutant variant comprises a signal sequence domain, followed by a chimeric tetrapeptide, followed by a tripeptide, followed by a kringle 2 domain, followed by a serine protease domain and a substituted amino acids at position 128-131. The substituted amino acids are AAAA (SEQ ID NO: 3) amino acids. The chimeric tetrapeptide is Gly-His-Arg-Pro (SEQ ID NO: 1). The chimeric tetrapeptide is at a position of 36 to 39 amino acid of the mutant variant. The tripeptide is Ser-Tyr-Glu. According to an embodiment herein, a chimeric truncated and mutant variant of a tissue plasminogen activator comprises a native t-pa deleted with Finger domain, a Growth Factor domain and a Kringle 1 domain, a chimeric tetrapeptide and a substituted amino acids at a position of 128-131.

The present invention provides a xylanase, or a modified xylanase enzyme comprising at least one substituted amino acid residue at a position selected from the group consisting of amino acid 11, 116, 118, 144 and 161, the position determined from sequence alignment of the modified xylanase with Trichoderma reesei xylanase II amino acid sequence. The xylanases described herein exhibit improved thermophilicity, alkalophilicity, expression efficiency, or a combination thereof, in comparison to a corresponding native xylanase.

The invention discloses a selenium enriched soy and a preparation method thereof. The preparation method comprises the following steps: (1) mixing raw materials with water, after the raw materials are cooked, cooling the raw materials to a temperature of 40 DEG C or less, inoculating 0.2 to 0.4% of mould starter to the raw materials, and mixing raw materials with liquefied mash to obtain a liquefied mash mixture (A) wherein the raw materials comprise soybean meal, wheat, wheat bran, and selenium-enriched mushroom; (2) subjecting the obtained liquefied mash mixture (A) to solid fermentation for 15 to 25 days at a temperature of 40 to 50 DEG C so as to obtain a liquefied mash mixture (B); (3) mixing the liquefied mash mixture (B) with 0.2 to 0.4% of selenium enriched yeast and brine, and carrying out fermentation for at least 30 days at a temperature of 25 to 35 DEG C to obtain liquefied mash mixture (C); (4) soaking liquefied mash mixture (C), spraying oil on liquefied mash mixture (C), and subjecting liquefied mash mixture (C) to pasteurization. The prepared selenium enriched soy contains selenium-substituted amino acid, which can be easily stored, absorbed and utilized by human tissues.