8-l-Cystinyl Bis(1,8-diazaspiro[4.5]decane) as an Orally Bioavailable l-Cystine Crystallization Inhibitor for Cystinuria

Cystinuria, a rare genetic disorder, is characterized by defective l-cystine reabsorption from the renal proximal tubule, resulting in abnormally high concentrations of l-cystine and subsequent l-cystine crystallization in urine and stone formation in the urinary tract. Inhibition of l-cystine crystallization by l-cystine diamides such as LH708 (