SEARCH Articles Figures Tables Biological activity chemical structure Biological systems, chemical equilibrium active transport Biologically active chemical Biologically active chemical Biologically active principles, chemical Biologically active principles, chemical elucidation Chemical Structures and Biological Activity of Natural Diterpene QMs Chemical activity Chemical properties translation into biological activity Chemical structure-biological activity relations using pattern recognition Chemically active Microbial Secondary Metabolites with Unique Biological Activity and Chemical Diversity Physical-Chemical Factors and Biological Activities Relationships between Chemical Structure and Biological Activity The Law of Mass Action, binding sites and receptors—understanding why specific, potent biological activity is a rare property for any one chemical to possess