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Keywords from Image Description:
Sildenafil. Skeletal formula of sildenafil Viagra ethoxy dihydromethyl oxopropylHpyrazolo dpyrimidinyl phenylsulfonylmethylpiperazine citrate Author date of creation self made by Ben Mills at March UTC Source usercreated image Comments highresolution black and white ChemDraw Photoshop en MattKingston en Later versions were