【Chemical name】：But-3-en-3-olide 4-methylideneoxetan-2-one
【CAS RN】： 674-82-8 【EINECS RN】：211-617-1
【Molecular formula】：C4H4O2 【Molecular weight】：84.07
【Main usage】：It is lively as raw materials of diacetyl , also used for dye, pigment, pharmaceutical intermediate and herbicide.
