The ZINC15 database is an updated version of ZINC12 and contains over 100 million purchasable compounds for virtual screening.
How to download molecules by catalog?
For zinc 15 it is recommended that we download small-molecule libraries across different vendors with user-specified properties (e.g. pH, formal charge, purchasability) using the "tranche browser" tool.
A general stepwise instruction can be found at Download by catalog
If you would like to download compounds from ChemDiv, The ZINC ID mapping:
The lead-like tranche:
Ref: reference models (dominate form at pH7.4) Mid: additional forms present at pH7.4