Abstract: The invention relates to new pyrazolo[1,5-a]pyrimidine derivatives of formula (I) or pharmaceutically acceptable salts, biologically active metabolites, pro-drugs, racemates, enantiomers, diastereomers, solvates and hydrates thereof that serve as GABAB receptor positive allosteric modulators. The invention also relates to the process for producing such compounds and key intermediates used in the process. The invention further relates to pharmaceutical compositions comprising such compounds optionally in combination with two or more different therapeutic agents and the use of such compounds in methods for treating diseases and conditions mediated and modulated by the GABAB receptor positive allosteric mechanism. The invention also provides a method for manufacture of medicaments useful in the treatment of such disorders.

Abstract: The invention relates to thiadiazine derivatives, or pharmaceutically acceptable salts, biologically active metabolites, pro-drugs, racemates, enantiomers, diastereomers, solvates and hydrates thereof, as well as to pharmaceutical compositions containing them and to their use as modulators of ?7 nicotinic acetylcholine receptor activity in a mammalian subject Formula (I):