Compounds of general formula (1)
R1—X1—W—X2—Z1—Z2—R2
or salts thereof, exhibiting preventive and therapeutic effects against HIV infectious diseases wherein R1 is an optionally substituted five- or six-membered ring group; X1 is a free valency or the like; W is a divalent group represented by, e. g., general formula (2)
(wherein A and B are each an optionally substituted five- to seven-membered ring; E1 and E4 are each optionally substituted carbon or the like; E2 and E3 are each oxygen or the like; and a and b are each a single bond or a double bond); X2 is a divalent group constituting a straight chain moiety; Z1 is a divalent cyclic group or the like; Z2 is a free valency or the like; and R2 is optionally substituted amino or the like.