API & Intermediate

Nitrofurazone appears as odorless pale yellow needles or yellow powder. pH (saturated aqueous solution) 6.0 - 6.5. Alkaline solutions are dark orange. (NTP, 1992) Nitrofurazone is a semicarbazone resulting from the formal condensation of semicarbazide with 5-nitrofuraldehyde. A broad spectrum antibacterial drug, although with little activity against Pseudomonas species, it is used as a local application for burns, ulcers, wounds and skin infections. It has a role as an antibacterial drug. It is a semicarbazone and a nitrofuran antibiotic. A topical anti-infective agent effective against gram-negative and gram-positive bacteria. It is used for superficial WOUNDS AND INJURIES and skin infections. Nitrofurazone has also been administered orally in the treatment of TRYPANOSOMIASIS.

Letrozole is a new generation of highly selective aromatase inhibitor, which is a synthetic benzyltriazole derivative. By inhibiting aromatase, letrozole can reduce the level of estrogen, so as to eliminate the stimulating effect of estrogen on tumor growth. The in vivo activity is 150-250 times stronger than that of the first generation aromatase inhibitor amlumide. Because of its high selectivity, it does not affect the function of glucocorticoid, mineralocorticoid and thyroid. High dose use has no inhibitory effect on the secretion of adrenal corticosteroids, so it has a high therapeutic index. Preclinical studies have shown that letrozole has no potential toxicity, mutagenic and carcinogenic effects on various systems and target organs of the body, and has less toxic and side effects, good tolerance. Compared with other aromatase inhibitors and anti estrogen drugs, letrozole has stronger anti-tumor effect. It is suitable for the treatment of patients with advanced breast cancer who are not effective in the treatment of estrogen and early treatment of breast cancer.

Lipoic acid is an endogenous antioxidant, which can remove the body's free radicals, promote the body's synthesis of vitamin C using glucose, and promote the synthesis of glutathione, effectively remove melanin, and assist coenzyme in physiological metabolism conducive to the body's immunity. Lipoic acid also has anti-inflammatory effect, can inhibit the activities of kinase, transforming factor, tumor necrosis factor and collagenase, and has anti-aging effect. Lipoic acid can preserve and regenerate other antioxidants and has a good health function to human body. It is widely used in the prevention and treatment of heart disease, diabetes, liver disease and Alzheimer's disease. The two enantiomers of lipoic acid showed different biological activities. Among them, R-type enantiomers are more effective than S-type enantiomers, which may be due to the fact that a large amount of R-type lipoic acid can enter cells and mitochondria through cell membrane and mitochondrial membrane and be reduced to dihydrolipoic acid, while only a small amount of S-type can enter cells and be reduced. Dihydrolipoic acid has stronger antioxidant capacity than lipoic acid. The regeneration of endogenous antioxidants and the repair of oxidative damage can only be achieved by dihydrolipoic acid.

4,6-dichloro-2 - (propylthio) - 5-aminopyrimidine is a pharmaceutical intermediate, which can be used as the intermediate of anticoagulant drug ticagrel.

Mirabelon tablets, developed by Estelle pharmaceutical company of Japan, were listed in Japan on September 16, 2011 and approved by the US Food and Drug Administration (FDA) on June 28, 2012 for the treatment of adult overactive bladder (OAB). Mirabelon was the first to be used to treat overactive bladder β 3. Adrenoceptor agonists, whose successful marketing fills the gap β There is a blank of adrenoceptor agonists in the treatment of overactive bladder.