Patent ID: 6894075

Claim:
A compound of the following formula (1): in which R represents -A-NH 2 ; —NH—R 1 ; phenyl-C 2-4 alkenyl unsubstituted or substituted by 1 to 5 C 1-4 alkoxy; benzyl unsubstituted or substituted by amino or diC 1-4 alkylamino; straight-chain or branched C 1-21 alkyl, C 15-21 alkenyl, C 15-21 alkadienyl, C 15-21 alkatrienyl, C 15-21 alkatetraenyl, or C 15-21 alkahexaenyl; retinyl; or C 5-15 carboxyalkyl, wherein A represents amino acid residue, —(CH 2 ) n1 —; or —(CH 2 ) n2 —C 6 H 5 , n1 denotes an integer of 2 to 8, n2 denotes an integer of 1 to 4, and R 1 represents straight-chain or branched C 1-4 alkyl unsubstituted or substituted by substituent(s) selected from a group consisting of halogen and hydroxy; cycloalkyl; haloacetyl; allyl; phenyl unsubstituted or substituted by substituent(s) selected from a group consisting of halogen, C 1-4 alkoxy, C 1-4 alkyl and C 1-4 alkylthio; benzyl; benzoyl; or benzenesulfonyl, or a geometric isomer thereof.