Synthesis and biological evaluation of analogues of butyrolactone I and molecular model of its interaction with CDK2Electronic supplementary information (ESI) available: general experimental procedure for preparation, physical and spectral characterizations (1H/13C NMR, mass spectrometry, and IR data) of compounds 1a?h, 4c, 4f, 4h, 5c?f, 5h, and 7d?e. AMBER parameters and partial atomic charges for butyrolactone I (Tables 2 and 3). Docking parameters (Table 4). See http://www.rsc.org/suppdata/ob/b4/b403052d/