Acta Cryst. (2012). E68, o41-o42 [ doi:10.1107/S1600536811051890 ]
Abstract: In the crystal structure of kallolide A acetate pyrazoline [systematic name: 7-methyl-16-oxo-4,10-bis(prop-1-en-2-yl)-17,18-dioxa-14,15-diazatetracyclo[184.108.40.206,9.01,12]octadeca-6,8,14-trien-5-yl acetate], C23H28N2O5, there is a 12-membered carbon macrocyclic structure. In addition, there is a trisubstituted furan ring, an approximately planar -lactone ring [maximum deviation of 0.057 (3) Å] and a pyrazoline ring, the latter in an envelope conformation. The pyrazoline and the -lactone rings are fused in a cis configuration. In the crystal, molecules are linked by weak C-HO interactions, forming a two-dimensional network parallel to (001). An intramolecular C-HO hydrogen bond is also present.
Online 7 December 2011
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