Abstract: An object of the present invention is to provide a bisphosphonic acid derivative and said bisphosphonic acid derivative being labeled with a radioactive nuclide, which has properties of rapid accumulation to the bone and rapid urinary excretion. The present invention relates to a bisphosphonic acid derivative and said bisphosphonic acid derivative being labeled with a radioactive nuclide, which is represented by the following general formula (1), R—Y—A  (1) wherein A is a bisphosphonic acid or a salt thereof, having P—C—P bond; Y is a bonding portion such as a methylene, an amido etc.

Abstract: A peptide having affinity with tumor or a salt thereof, which comprises an amino acid sequence containing 20 or less amino acid residues, said amino acid sequence being described as X.sub.1 -YCAREPPT-X.sub.2 wherein A, C, E, P, R, T and Y represent amino acid residues expressed by standard one-letter symbols, each of amino acid residues A, C, R and Y in the amino acid sequence YCAR may be in either L-form or D-form, X.sub.1 represents a basic organic compound having 1-3 amino groups, and X.sub.2 represents any given amino acid sequence, is provided together with a radioactive diagnostic agent and a radioactive therapeutic agent containing the above peptide or a salt thereof. The present tumor affinity peptide is high in radioactive metal labeling yield, useful for imaging and treating pathological tissues such as of breast cancer, ovarian cancer and colon cancer of mammals including human, and difficult to be readily metabolized in organisms and to accumulate in normal tissues especially at kidney and liver.

Abstract: A peptide having affinity with inflammation is disclosed, which contains at least one of the following amino acid sequences:LLGGPS (SEQ ID NO:1),LLGGPSV (SEQ ID NO:2),KEYKAKVSNKALPAPIEKTISK (SEQ ID NO:3),KEYKCKVSNKALPAPIEKTISK (SEQ ID NO:4),KTKPREQQYNSTYR (SEQ ID NO:5), andKTKPREQQYNSTYRVV (SEQ ID NO:6),wherein A, C, E, G, I, K, L, N, P, Q, R, S, T, V, and Y represent amino acid residues expressed by standard one-letter symbols. According to the present invention, a peptide and its chemically modified substances, radioactive metal labeled peptides derived therefrom, and radioactive diagnostics comprising such peptide are provided, which are useful for imaging inflammation region and easy in preparation handling, and accumulate at inflammation site immediately after administration while being excellent in clearance into urine. The imaging is possible in several ten minutes after administration.

Abstract: The invention provides, inter alia, metal radionuclide-labelled reagent comprising a metal radionuclide coordinated with a metal chelate forming peptide having an amino acid sequence of three amino acid residues represented by: X1-X2-Cys, wherein X1 represents an Asp residue, a Tyr residue or a Lys residue; X2 represents an amino acid residue other than a Cys residue and a Pro residue, provided that X2 does not represent a Gly residue when X1 represents an Asp residue; wherein functional groups at the N-terminus, C-terminus and side chain may be optionally substituted with protecting groups; and wherein each of the amino acid residues may be either D-form or L-form.

Abstract: The invention provides a metal chelate forming peptide having an amino acid sequence of three amino acid residues represented by: X1-X2-Cys, wherein X1 represents an amino acid residue other than Cys residue; X2 represents an amino acid residue other than Cys residue and Pro residue; functional groups at the N-terminus, C-terminus and side chain may be substituted with protecting groups; and each of the amino acid residues may be any of D-form and L-form. Further, the invention provides a complex of the peptide with a physiologically active peptide, protein or other substance; a labeled reagent obtained by labeling the peptide or the complex with a metal radionuclide; and a radiodiagnostic and radiotherapeutic composition comprising the metal radionuclide-labeled reagent.