Medicinal chemistry advances of SGLT inhibitors: SAR, structural innovation, and mechanistic insights

Sodium-glucose co-transporter (SGLT) inhibitors originated as simple C-aryl glucosides but have gradually evolved into clinically proven compounds benefiting metabolism, cardiovascular and kidney function. Between 2010 and 2025, substantial progress has been made in their medicinal chemistry, structural diversification, and mechanistic understanding. This review highlights major developments in structure-activity relationships (SAR), scaffold innovation, and structure-guided design that have shaped modern SGLT inhibitors. Early studies focused on establishing a metabolically stable C-aryl glucoside scaffold, revealing that the positioning of proximal and distal aryl groups, linker rigidity, and sugar-binding interactions critically influence activity. Subsequent efforts incorporated heteroaryl systems, fluorinated analogues, carba-sugars, and macrocyclic frameworks improved SGLT2 potency, SGLT2/SGLT1 selectivity, and overall drug-like properties. Further advances introduced N-glucosides, difluoro glycomimetics, l-xylose-based inhibitors, thioglucoside mimics, gut-restricted SGLT1 inhibitors, steroid-derived heterocycles, benzyl-modified C-glucosides, and dual-target designs like SGLT2-glycogen phosphorylase hybrids. More recent work has emphasized next-generation scaffolds, enhanced selectivity, oral bioavailability, multifunctional molecules, and cryo-EM-guided design based on high-resolution structures of SGLT1 and SGLT2-MAP17, clarifying sugar recognition, vestibule interactions, and isoform-specific inhibition. Taken together, these advances provide a coherent view of SGLT inhibitor evolution and offer a framework for designing the next-generation of SGLT-based therapies for diabetes and related cardiometabolic and renal disorders.