MeSH

A pyrimidine analog that is an antineoplastic antimetabolite. It interferes with DNA synthesis by blocking the THYMIDYLATE SYNTHETASE conversion of deoxyuridylic acid to thymidylic acid.

Agents that suppress immune function by one of several mechanisms of action. Classical cytotoxic immunosuppressants act by inhibiting DNA synthesis. Others may act through activation of T-CELLS or by inhibiting the activation of HELPER CELLS. While immunosuppression has been brought about in the past primarily to prevent rejection of transplanted organs, new applications involving mediation of the effects of INTERLEUKINS and other CYTOKINES are emerging.

Year introduced: 1966(1964)

Drugs that are chemically similar to naturally occurring metabolites, but differ enough to interfere with normal metabolic pathways. (From AMA Drug Evaluations Annual, 1994, p2033)

Antimetabolites that are useful in cancer chemotherapy.

Year introduced: 1975

One of four nucleotide bases in the nucleic acid RNA.

Heterocyclic compounds known as 2-pyrimidones (or 2-hydroxypyrimidines) and 4-pyrimidones (or 4-hydroxypyrimidines) with the general formula C4H4N2O.

Year introduced: 1968(1966)

A family of 6-membered heterocyclic compounds occurring in nature in a wide variety of forms. They include several nucleic acid constituents (CYTOSINE; THYMINE; and URACIL) and form the basic structure of the barbiturates.

Year introduced: THONZYLAMINE was heading 1972-1984 (Prov 1972)

Organic compounds that contain a ring structure made up of carbon and one or more additional elements such as nitrogen and oxygen.

Year introduced: 1998

Cyclic compounds that include atoms other than carbon in their ring structure.

A group of pharmacologic activities, effects on living systems and the environment, and modes of employment of drugs and chemicals. They are broken into actions, which describe their effects, and uses, which describe how they are employed.

Year introduced: 1999

Agents capable of exerting a harmful effect on the body.

Year introduced: 1998

Uses of chemicals which affect the course of conditions, diseases, syndromes or pathology to benefit the health of an individual.

Year introduced: 2004

Biologically active substances whose activities affect or play a role in the functioning of the immune system.

Year introduced: 1998

A broad category of chemical actions and uses that result in the prevention, treatment, cure or diagnosis of disease. Included here are drugs and chemicals that act by altering normal body functions, such as the REPRODUCTIVE CONTROL AGENTS and ANESTHETICS. Effects of chemicals on the environment are also included.

Year introduced: 2004(1999)

A broad category of chemical actions with harmful or deadly effect on living organisms.

Year introduced: 2004(1998)

Substances that inhibit or prevent the proliferation of NEOPLASMS.

Pharmacological activities at the molecular level of DRUGS and other exogenous compounds that are used to treat DISEASES and affect normal BIOCHEMISTRY.

Year introduced: 2008(2004)

Activities which affect organs and systemic functions without regard to a particular disease.

Year introduced: 2004