As one of the main manufacturer and exporter of carvedilol and its intermediates in China, we supply the best quality and price. 4-hydroxy carbazole4-hydroxy carbazole CAS No. [52602-39-8] [Structure]: Appearance Off-white crystalline powderMP 169 -- 171 °C Assay ≥ 99.0%Water ≤ 0.5%1,2,3,9-tetrahydro-4H-Carbazole-4-one ≤1.0%