8-Azaguanine is a purine analog which resembles guanine close enough to compete with it in the metabolism of living organisms. It has been widely studied and has shown to cause retardation of some malignant neoplasms when administered to tumors in animals. It has been used for the treatment of patients with leukemia.

Temperocol is an investigative anti-cancer drug that inhibits the expression of survivin and CDK-1; discovered at Johns Hopkins University and under development by Erimos Pharmaceuticals. It has been tested in phase I/II clinical trials for Leukemia, and several forms of neoplasms including gliomas. Results of these clinical trials have shown promise, however treatment regimes produce several toxic side effects that need to be balanced against efficacy. Temperocol is a fully methylated derivative of the natural product Nordihydroguaiaretic acid.

SGI-1776 is a PIM-kinase inhibitor, developed by SuperGen Inc. SGI-1176 was tested in clinical trials against relapsed/refractory leukemias, prostate cancer and Non Hodgkin's Lymphoma, but the dose limiting toxicity of cardiac QTc prolongation was identified and clinical development of SGI-1776 was terminated.

Obatoclax (GX15-070) is a novel BH3 mimetic pan Bcl- 2 inhibitor. The clinically studied formulation is as obatoclax mesylate (Box 1), a salt. It is only under study as an intravenous preparation. It functions to block BH3-mediated binding of Bcl-2, Bcl-XL, Mcl-1 and A1 to Bax and Bak. Bax and Bak thus are unopposed and able to dimerize to allow initiation of intrinsic apoptosis. Preclinically, obatoclax has been shown to reverse inhibition of Bax or Bak by Bcl-2, Bcl-XL, Bcl-w and Mcl-1. Obatoclax was discovered by Gemin X, which was acquired by Cephalon, which has since been acquired by Teva Pharmaceuticals. Obatoclax had been in phase III clinical trials by Gemin X Biotechnologies (subsidiary of Teva) for the treatment of non-small lung cancer (NSCLC). The compound received orphan drug designation in the U.S. in 2004 for the treatment of chronic lymphocytic leukemia (CLL). However, Teva discontinued the development of obatoclax in 2013.

E7107 is a semisynthetic derivative of the natural product pladienolide B which was originally isolated from Streptomyces platensis. E7107 is the first compound a new class of anti-cancer agents targeting the spliceosome. Specifically E7107 interacts with the Splicing factor 3B subunit 1 (SF3b1) to block the normal splicing of oncogenes. Development of E7107 was suspended after Phase I clinical trials due to an unacceptable profile of adverse events.

Disogluside (Trillin) is an active ingredient isolated from Dioscorea nipponica Makino. Trillin reduces liver chronic inflammation and fibrosis in carbon tetrachloride (CCl4) induced liver injury in mice. Trillin exhibited protective effect on LPS-induced ALI by the regulations of related inflammatory events via the activations of Nrf2, HO-1 and NF-κB pathway. Trillin has being shown to exert protective effects against hyperlipidemia and oxidative stress. Trillin induced multinucleation in HL-60, NB4 and K562 cells, indicating it could induce mitotic arrest in these leukemia cells.

Pyroxamide is a potent histone deacetylase (HDAC) inhibitor. Pyroxamide induced terminal differentiation in murine erythroleukemia (MEL) cells and inhibited the growth by cell cycle arrest or apoptosis in a variety of tumor cells. An accumulation of acetylated histones and increased levels of p21/WAF1 expression were detected in cancer cells and in prostate xenografts treated with Pyroxamide.

18alpha-Glycyrrhetinic acid (18-GA), a derivative of enoxolone, is used to inhibit gap junctions and furthermore, it has anti-proliferative properties against various cancer types by affecting the cell cycle proteins. 18alpha-Glycyrrhetinic acid, is a non-selective inhibitor of 11beta-hydroxysteroid dehydrogenases isozymes and results in increased whole body insulin sensitivity and decreased glucose production.

Nobiletin is a flavanoid isolatable from citrus peels. It has demonstrated anti-cancer properties in several in vitro cell models and garnered interest as a potential treatment for the motor and cognitive symptoms of Parkinson's disease. However, investigation of this compound has not moved beyond animal studies.

Mertansine (Maytansine) is a 19–member ansa macrolide structure attached to a chlorinated benzenering. It was originally isolated from the shrub Maytenus ovatus. Mertansine (DM1) is a tubulin inhibitor, it inhibits the assembly of microtubules by binding to tubulin, with a linker structure can create an antibody-drug conjugate (ADC). Mertansine is a potent microtubule-targeted compound that induces mitotic arrest and kills tumor cells at sub-nanomolar concentrations. The antimitotic effect of maytansine has been attributed to its ability to inhibit microtubule assembly by binding to tubulin with a KD of ~ 1 umol/L, at or near the vinblastine-binding site. Experimental ADCs with the SPP-DM1 design include lorvotuzumab mertansine. DM1 can also be linked to an antibody using the SMCC (4-(3-mercapto-2,5-dioxo-1-pyrrolidinylmethyl)-cylohexanecarboxylic acid) linker, in which case the International Nonproprietary Name of the conjugate formed contains the word emtansine. DM1 and its attachment via these linkers result from ImmunoGen Inc research. Trastuzumab emtansine (T-DM1) is an anti-HER2/neu antibody-drug conjugate.