Abstract: A compound represented by formula (I); a process for producing a compound (substance F-1490) of formula (I), wherein X represents —O— and R represents a hydroxyl group, by using a microorganism belonging to the genus Cunninghamella; and a Cunninghamella sp. F-1490 strain (FERM BP-8287) capable of producing the substance F-1490; and an osteoclast differentiation inhibitory agent containing as an active ingredient the compound represented by formula (I): wherein X represents —O— or —CH2—, and R represents a hydroxyl group when X represents —O—, or a hydrogen atom when X represents —CH2—.

Abstract: Compounds represented by formula (I) below; a process for producing the compounds by culturing a microorganism belonging to the genus Aspergillus and isolating the above-mentioned compounds from the culture; an angiogenesis inhibitory agent containing as an active ingredient the compounds; and an Aspergillus sp. F-1491 (FERM BP-8288) strain capable of producing the compounds. In formula (I), R represents a methyl group or an ethyl group, R1 represents a hydrogen atom, a chlorine atom, a hydroxyl group or a methoxy group, R2 represents a hydroxyl group, or R1 and R2 taken together form an epoxy ring structure.

Abstract: A compound represented by formula (I); a process for producing a compound (substance F-1490) of formula (I), wherein X represents —O— and R represents a hydroxyl group, by using a microorganism belonging to the genus Cunninghamella; and a Cunninghamella sp. F-1490 strain (FERM BP-8287) capable of producing the substance F-1490; and an osteoclast differentiation inhibitory agent containing as an active ingredient the compound represented by formula (I): wherein X represents —O— or —CH2—, and R represents a hydroxyl group when X represents —O—, or a hydrogen atom when X represents —CH2—.

Abstract: The present invention discloses a new .alpha.-keto amide derivative or a salt thereof represented by the formula (1): ##STR1## wherein X represents (1) a peptide residue or amino acid residue in which the functional group may be protected, (2) a hydrogen atom or (3) an amino-protective group, Y represents a peptide residue or amino acid residue in which the functional group may be protected, E represents a substituent on the alkylene (C.sub.n H.sub.2n-1) and is a halogen, lower alkoxy or hydrogen, A represents a carbonyl group or mono- or di-substituted methylene (the substituent being a hydroxy, lower alkoxy, phenylimino or benzylimino), and n represents an integer of 2 to 6.The compound of the present invention is effective in inhibiting prolyl endopeptidase activity and useful as an active ingredient of an enzyme inhibitor.

Abstract: A protease adsorbent wherein valyl-glycyl-argininal is bound to a water-insoluble carrier and a process for purifying TPA utilizing the same.

Abstract: A biospecific adsorbent comprising pyroglutamyl-lysyl-leucyl-argininal combined with a water-insoluble support is provided. This biospecific adsorbent is useful as an adsorbent for use in affinity chromatography and can be utilized for the purification of proteases such as urokinase.

Abstract: L-Argininal derivatives of the general formula: ##STR1## are disclosed. A method of manufacturing any such derivative is also disclosed. The L-argininal derivative of this invention has a strong inhibitory activity on proteases, such as serine and thiol proteases, and is expected to provide useful medicines, including those which are effective for diseases caused by abnormal elevation of protease activity.