<prompt> True about CyclophosphamideAntimetabolitesAlkylating agentPlatinum compoundTopoisomerase inhibitors  <response>: Ans. b Alkylating agentRef. katzung 9th ed. 1280; KDT 819-820 Cyclophosphamide is the most widely used alkylating agent. It is an inactive compound. Transformation into active metabolite occurs in liver, and a wide range of anti tumor action is exerted. It has prominent immunosuppressant property, so it has been particularly utilized in bone marrow transplantation. In other organ transplants it is employed only as a reserve drug. Drugs of different category are:Alkylating agentsAntimetabolitesPlatinum compoundTopo-isomerase inhibitors Cyclophosphamide Ifosfamide Mechlorethamine Melphalan Busulfan Procarbazine Nitrosourea Carmustine Lomustine semustineFolic acid antagonist MethotrexatePurine analogues 6 Mercaptopurine 6thioguanine Cladribine FludarabinePyrimidine analogues Capecitabin Gemcitabin Cyatarabine and 5 FU Cisplatin Carboplatin OxaliplatinTOPOISOMERASE-I IrinotecamTOPOISOMERASE-II Etoposide Anthracycline Doxorubicin daunorubicin 