Abstract: [Problem] To provide a guanidine derivative (in particular, an amino acid compound having a 4-guanidino group) which has a low production cost and is less likely to cause the problem of waste liquor, a method for producing the same and an intermediate to be used in the production of the same. [Solution] A compound represented by formula (I), a tautomer thereof, an enantiomer thereof, a pharmaceutically acceptable salt thereof or a pharmaceutically acceptable solvate thereof; a method for producing a compound represented by formula (I), a tautomer thereof, an enantiomer thereof, a pharmaceutically acceptable salt thereof or a pharmaceutically acceptable solvate thereof, said method comprising a mixing step for mixing a compound represented by formula (II) with a compound represented by formula (III); and a compound represented by formula (IV) or formula (V).

Abstract: A novel amino acid derivative is provided, wherein the amino acid derivative is expected to improve binding affinity of polypeptides comprising the derivative therein.

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

Abstract: [Problem] To provide a compound having a 15-PGDH inhibitory effect. [Solution] A compound represented by general formula (1) or a pharmacologically acceptable salt thereof.

Abstract: The present technology generally relates to peptides that bind to the growth hormone receptor (GhR), to peptides that bind to the GhR and have antagonistic activity, and to compositions comprising such peptides.

Abstract: The present invention is to provide a method for producing a peptide containing an N-alkylamino acid, which comprises the following Steps (1) to (3). Step (1): a step of mixing an N-terminal protected amino acid or an N-terminal protected peptide with a carboxylic acid halide or a halogenated alkyl formate; Step (2): a step of mixing an amino acid or a peptide in which the N-terminal and the C-terminal are not protected with a trialkylsilylating agent; and Step (3): a step of mixing the product obtained in Step (1) with the product obtained in Step (2).

Abstract: To provide a novel mutilin derivative having a substitution at the 14-position, which is a novel mutilin analogue exhibiting a potent and broad antimicrobial action against Gram-positive bacteria and Gram-negative bacteria including various drug-resistant bacteria, and which is expected to be useful as an agent for treating infectious diseases. A mutilin derivative represented by the following general formula (1): or a pharmaceutically acceptable addition salt thereof.

Abstract: To provide a novel mutilin derivative having a substitution at the 14-position, which is a novel mutilin analogue exhibiting a potent and broad antimicrobial action against Gram-positive bacteria and Gram-negative bacteria including various drug-resistant bacteria, and which is expected to be useful as an agent for treating infectious diseases. A mutilin derivative represented by the following general formula (1): or a pharmaceutically acceptable addition salt thereof.