Borneol-mediated vardenafil hydrochloride patch for pediatric pulmonary arterial hypertension: Preparation, characterization and in vivo study.

Background: Pediatric pulmonary arterial hypertension (PPAH) is a malignant progressive rare disease characterized by restricted pulmonary artery blood flow and progressively increasing blood pressure, which has shorter survival time of only about 10 months as compared to adults. Previous studies have shown that low-dose vardenafil hydrochloride (Var) could significantly improve the symptoms of PPAH. However, Var is currently available only in tablet form in the market for erectile dysfunction, and no special preparation is available for PPAH.

Synthesis of High Purified Tulobuterol and Its Study of the Organic Impurities.

The synthetic condition of tulobuterol was optimized to gain lower impurity content. Two intermediates were analyzed, and three degradation impurities were isolated using preparative liquid chromatography for the first time and subsequently characterized by various techniques. Possible degradation impurities were deduced by an oxidative mechanism.