21 sounds rather a lot to me can you post some of the structures you came up with?
Here's the
eight NIST came up with:
Oxirane, (chloromethyl)- (C3H5ClO)
2-Propanone, 1-chloro- (C3H5ClO)
Propanoyl chloride (C3H5ClO)
Oxirane, (chloromethyl)- (C3H5ClO)
Oxirane, (chloromethyl)-, (R)- (C3H5ClO)
2-Chloro-2-propen-1-ol (C3H5ClO)
(S)-(+)-Epichlorohydrin (C3H5ClO)
3-chloro-2-propen-1-ol (C3H5ClO)