The present invention provides a method for producing a carbamate that includes a step (1) and a step (2) described below: (1) a step of producing a compound (A) having a urea linkage, using an organic primary amine having at least one primary amino group per molecule and at least one compound selected from among carbon dioxide and carbonic acid derivatives, at a temperature lower than the thermal dissociation temperature of the urea linkage; and (2) a step of reacting the compound (A) with a carbonate ester to produce a carbamate.

The invention relates to a process for preparing a diisocyanate of the formula (A) ##STR00001## where R is selected from the group consisting of alkyl, aryl, and combinations thereof, comprising the following process steps in the indicated order; 1) providing an intermediate of the formula (B) with a process using lysine and urea ##STR00002## and where R and each R′ are independently selected from the group consisting of alkyl, aryl, and combinations thereof; and 2) thermolytic cleavage of the intermediate of the formula (B), thereby affording the diisocyanate of the formula (A),
and also to the diisocyanate directly prepared therewith.

The invention relates to a process for preparing a diisocyanate of the formula (A) ##STR00001## where R is selected from the group consisting of alkyl, aryl, and combinations thereof, comprising the following process steps in the indicated order; 1) providing an intermediate of the formula (B) with a process using lysine and urea ##STR00002## and where R and each R′ are independently selected from the group consisting of alkyl, aryl, and combinations thereof; and 2) thermolytic cleavage of the intermediate of the formula (B), thereby affording the diisocyanate of the formula (A),
and also to the diisocyanate directly prepared therewith.

A novel amino acid derivative is provided, wherein the amino acid derivative is expected to improve solubility of polypeptides comprising the derivative therein.

A novel amino acid derivative is provided, wherein the amino acid derivative is expected to improve solubility of polypeptides comprising the derivative therein.

The present disclosure describes compounds of Formula (I) and pharmaceutically acceptable salts thereof:

##STR00001##

The present disclosure describes compounds of Formula (I) and pharmaceutically acceptable salts thereof:

##STR00001##

Disclosed is use of an aspartic acid derivative having a structure represented by formula (I), or a racemate, stereoisomer, geometric isomer, tautomer, solvate or feed-acceptable salt thereof, in preparing an animal feed additive that significantly improves production performance of farmed animals,

##STR00001##

wherein Y and X are independently selected from a C.sub.1-C.sub.20 alkyl or —H; R.sup.1 is R.sup.1aC(═O) or H; R.sup.2 is R.sup.2aC(═O); and the R.sup.1a and R.sup.2a are independently selected from (A)(B)N—(CH.sub.2).sub.0-5—, and the A and B are independently selected from a C.sub.1-C.sub.20 alkyl or —H.

Disclosed is use of an aspartic acid derivative having a structure represented by formula (I), or a racemate, stereoisomer, geometric isomer, tautomer, solvate or feed-acceptable salt thereof, in preparing an animal feed additive that significantly improves production performance of farmed animals,

##STR00001##

wherein Y and X are independently selected from a C.sub.1-C.sub.20 alkyl or —H; R.sup.1 is R.sup.1aC(═O) or H; R.sup.2 is R.sup.2aC(═O); and the R.sup.1a and R.sup.2a are independently selected from (A)(B)N—(CH.sub.2).sub.0-5—, and the A and B are independently selected from a C.sub.1-C.sub.20 alkyl or —H.

Methods of improving athletic performance in a human, increasing the bioabsorption of the compound in a human, or of increasing the vasodilative characteristics in a human comprise administering to the human compositions and supplement formulations comprising a compound selected from the group consisting of Carnitine, Taurine, and derivative forms thereof; and a Nitrate are disclosed.