The present invention discloses triazene analogs of the general formula (I) and formula (II), their tautomeric forms, stereoisomers, polymorphs, hydrates, solvates, and pharmaceutically acceptable salts thereof for the metastatic malignant melanoma and other cancers including but not limited to lymphomas, sarcomas, carcinomas, and gliomas. The invention further discloses a process for the preparation of the above said triazene analogs of formula (I) and formula (II), and their pharmaceutically acceptable compositions.