Fig. 7From: Spectroscopic details on the molecular structure of pyrimidine‑2‑thiones heterocyclic compounds: computational and antiviral activity against the main protease enzyme of SARS-CoV-2MESP map of the optimized heterocyclic structures, a L1, b L2, c L3, d L4, e L5, where color mapped from red (highly negative charge value) to blue (highly positive charge value)Back to article page