Provided are a copolycarbonate having superior weather resistance as well as excellent mechanical properties, and a preparation method thereof.

Provided herein are nutritional, or therapeutic, compositions and methods of use in primarily treating kidney patients suffering from low serum albumin. The compositions are divided into four formulations, comprising: 1) the magnesium salt and/or the calcium salt of the alpha keto acids of: α-leucine, α-valine, α-isoleucine, α-phenylalanine, α-hydroxy methionine; and/or α-tryptophan, and/or α-tyrosine; 2) L-lysine monoacetate, L-threonine; and/or 3) histidine, tryptophan, and tyrosine, as amino acids or base acids. The specific formulation administered depends in part upon which stage 2-5 of renal disease the patient has. The invention further comprises methods of treatment of disorders associated with low serum albumin using the composition as an over-the-counter pill. The patient's serum albumin is tested on a periodic basis and the selected composition and dose are adjusted accordingly. And the invention comprises method of making α-leucine, α-valine, α-isoleucine, a-tyrosine and α-tryptophan in a multi-step process.

Provided herein are nutritional, or therapeutic, compositions and methods of use in primarily treating kidney patients suffering from low serum albumin. The compositions are divided into four formulations, comprising: 1) the magnesium salt and/or the calcium salt of the alpha keto acids of: α-leucine, α-valine, α-isoleucine, α-phenylalanine, α-hydroxy methionine; and/or α-tryptophan, and/or α-tyrosine; 2) L-lysine monoacetate, L-threonine; and/or 3) histidine, tryptophan, and tyrosine, as amino acids or base acids. The specific formulation administered depends in part upon which stage 2-5 of renal disease the patient has. The invention further comprises methods of treatment of disorders associated with low serum albumin using the composition as an over-the-counter pill. The patient's serum albumin is tested on a periodic basis and the selected composition and dose are adjusted accordingly. And the invention comprises method of making α-leucine, α-valine, α-isoleucine, a-tyrosine and α-tryptophan in a multi-step process.

Methods and reagents for esterification of biological molecules including proteins, polypeptides and peptides. Diazo compounds of formula I: ##STR00001##
where R is hydrogen, an alkyl, an alkenyl or an alkynyl, R.sub.A represents 1-5 substituents on the indicated phenyl ring and R.sub.M is an organic group, which includes a label, a cell penetrating group, a cell targeting group, or a reactive group or latent reactive group for reaction to bond to a label, a cell penetrating group, or a cell targeting group, among other organic groups are useful for esterification of biological molecules. Also provided are diazo compounds which are bifunctional and trifunctional coupling reagents as well as reagents for the synthesis of compounds of formula I.

Methods and reagents for esterification of biological molecules including proteins, polypeptides and peptides. Diazo compounds of formula I: ##STR00001##
where R is hydrogen, an alkyl, an alkenyl or an alkynyl, R.sub.A represents 1-5 substituents on the indicated phenyl ring and R.sub.M is an organic group, which includes a label, a cell penetrating group, a cell targeting group, or a reactive group or latent reactive group for reaction to bond to a label, a cell penetrating group, or a cell targeting group, among other organic groups are useful for esterification of biological molecules. Also provided are diazo compounds which are bifunctional and trifunctional coupling reagents as well as reagents for the synthesis of compounds of formula I.

A method for manufacturing 2-hydroxy-4-(methylthio)butyric acid (HMTBA) from 2-hydroxy-4-methylthio-butyronitrile (HMTBN), where HMTBN is hydrolyzed into HMTBA in the presence of a mineral acid in an aqueous medium, the medium is neutralized by addition of a base, a first phase including at least HMTBA and salts and a second phase containing salts are separated, the method including the separation of the HMTBA from the salts of the first phase, by subjecting the latter to a chromatography.

A method for manufacturing 2-hydroxy-4-(methylthio)butyric acid (HMTBA) from 2-hydroxy-4-methylthio-butyronitrile (HMTBN), where HMTBN is hydrolyzed into HMTBA in the presence of a mineral acid in an aqueous medium, the medium is neutralized by addition of a base, a first phase including at least HMTBA and salts and a second phase containing salts are separated, the method including the separation of the HMTBA from the salts of the first phase, by subjecting the latter to a chromatography.

A method for manufacturing 2-hydroxy-4-(methylthio)butyric acid (HMTBA) from 2-hydroxy-4-methylthio-butyronitrile (HMTBN), where HMTBN is hydrolyzed into HMTBA in the presence of a mineral acid in an aqueous medium, the medium is neutralized by addition of a base, a first phase including at least HMTBA and salts and a second phase containing salts are separated, the method including the separation of the HMTBA from the salts of the first phase, by subjecting the latter to a chromatography.

Compounds, compositions and methods are provided for inhibiting corrosion at a surface in the production, transportation, storage, and separation of fluids such as crude oil and natural gas, the compounds having the formula: ##STR00001## wherein: Each R.sub.1 is independently —CH.sub.2OH and —C(O)OH; R.sub.2 is ##STR00002## Each R.sub.3 is independently hydrogen or R.sub.5, or both R.sub.3 together form a ring via a linker ##STR00003## Each R.sub.4 is independently hydrogen or R.sub.5; R.sub.5 is —CH.sub.2SC.sub.2H.sub.4R.sub.1; and n is an integer from 0 to 3.

Compounds, compositions and methods are provided for inhibiting corrosion at a surface in the production, transportation, storage, and separation of fluids such as crude oil and natural gas, the compounds having the formula: ##STR00001## wherein: Each R.sub.1 is independently —CH.sub.2OH and —C(O)OH; R.sub.2 is ##STR00002## Each R.sub.3 is independently hydrogen or R.sub.5, or both R.sub.3 together form a ring via a linker ##STR00003## Each R.sub.4 is independently hydrogen or R.sub.5; R.sub.5 is —CH.sub.2SC.sub.2H.sub.4R.sub.1; and n is an integer from 0 to 3.