Introduction Viagra is used to relaxes the muscles and increase the blood flow in some specific part of our body. Viagra is the well know treatment for erectile dysfunction . This ED pill has been used by millions of men. It has been established itself as the leading brand for the effective treatment of impotence. Viagra restorespotency in men who are not able to gain or maintain an erection on the needed level. It is one of the most commonly sold drugs and people love the results. Viagra is a brand medicine for men who suffer from erectile. The pill is blue and diamond-shaped. The treatment is available in a different dosage. One pill can change your l boring life to exciting. Sildenafil is a generic version of Viagra. Ingredients in Viagra The preparation steps for sildenafil are: Carboxamide formation with refluxing thionyl chloride/NH4OH Methylation of 3-propylpyrazole-5-carboxylic acid ethyl ester with hot dimethly sulfate. Hydrolysis with aqueous sodiu...