Medchemexpress, HY-18299B 1mg (S)-Purvalanol B CAS: (S)-Purvalanol B is the S enantiomer of Purvalanol B. Purvalanol B is a cyclin-dependent kinase inhibitor. Purity:>98% Medchemexpress has over 10000 novel life-science reagents, reference compounds, APIs and natural compounds for laboratory and scientific use. Other quantity can also be offered.