由4个异戊二烯单位构成的结构类型是

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SQL Error: select id,body,options from ***_enewstiku where sourceid='29380' and id < 2393200 and id<>'2393200' order by id desc limit 5 SQL Error: select id,body,options from ***_enewstiku where sourceid='29380' and id > 2393200 and id<>'2393200' order by id asc limit 5