Streamlined Scalable Synthesis of 4-Bromo-6-chloro-5-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole: A Building Block
Xingyong Zhu1, Songren Xue1, Wencun Wang1
1PharmaBlock Sciences Nanjing , No. 81 Huasheng Road, Jiangbei New District, Nanjing210032, China.
The Journal of Organic Chemistry
|July 20, 2026
Abstract:
A practical, concise, and scalable synthetic route has been developed for the KRAS inhibitor building block 4-bromo-6-chloro-5-iodo-1-(tetrahydro-2H-pyran-2-yl)-1H-indazole. The route comprises six steps, four of which are telescoped, and requires no column chromatography purification. This optimized process has been successfully implemented for the large-scale production of building block 1 at up to ∼200 kg with an overall yield of 61.68%.


