Chemical Formula: C17H11N5

Chemical Formula C17H11N5

Found 5 metabolite its formula value is C17H11N5

Letrozole

Letrozole, Pharmaceutical Secondary Standard; Certified Reference Material

C17H11N5 (285.1014406)


Letrozole is a member of triazoles and a nitrile. It has a role as an antineoplastic agent and an EC 1.14.14.14 (aromatase) inhibitor. Letrozole, or CGS 20267, is an oral non-steroidal type II aromatase inhibitor first described in the literature in 1990. It is a third generation aromatase inhibitor like [exemestane] and [anastrozole], meaning it does not significantly affect cortisol, aldosterone, and thyroxine. Letrozole was granted FDA approval on 25 July 1997. Letrozole is an Aromatase Inhibitor. The mechanism of action of letrozole is as an Aromatase Inhibitor. Letrozole is a nonsteroidal inhibitor of aromatase which effectively blocks estrogen synthesis in postmenopausal women and is used as therapy of estrogen receptor positive breast cancer, usually after resection and after failure of tamoxifen. Letrozole has been associated with a low rate of serum enzyme elevations during therapy and rare instances of clinically apparent liver injury. Letrozole is a nonsteroidal inhibitor of estrogen synthesis with antineoplastic activity. As a third-generation aromatase inhibitor, letrozole selectively and reversibly inhibits aromatase, which may result in growth inhibition of estrogen-dependent breast cancer cells. Aromatase, a cytochrome P-450 enzyme localized to the endoplasmic reticulum of the cell and found in many tissues including those of the premenopausal ovary, liver, and breast, catalyzes the aromatization of androstenedione and testosterone into estrone and estradiol, the final step in estrogen biosynthesis. Letrozole (INN, trade name Femara®) is an oral non-steroidal aromatase inhibitor that has been introduced for the adjuvant treatment of hormonally-responsive breast cancer. Estrogens are produced by the conversion of androgens through the activity of the aromatase enzyme. Letrozole blocks production of estrogens in this way by competitive, reversible binding to the heme of its cytochrome P450 unit. The action is specific, and letrozole does not reduce production of mineralo- or corticosteroids. In contrast, the antiestrogenic action of tamoxifen, the major medical therapy prior to the arrival of aromatase inhibitors, is due to its interfering with the estrogen receptor, rather than inhibiting estrogen production. Letrozole is approved by the United States Food and Drug Administration (FDA) for the treatment of local or metastatic breast cancer that is hormone receptor positive or has an unknown receptor status in postmenopausal women. Side effects include signs and symptoms of hypoestrogenism. There is concern that long term use may lead to osteoporosis, which is why prescriptions of Letrozole are often accompanied by prescriptions of osteoporosis-fighting medication such as Fosamax. Letrozole has shown to reduce estrogen levels by 98 percent while raising testosterone levels. The anti-estrogen action of letrozole is preferred by athletes and bodybuilders for use during a steroid cycle to reduce bloating due to excess water retention and prevent the formation of gynecomastia related breast tissue that is a side effect of some anabolic steroids. Usage above 2.5 mg/day is known to potentially temporarily kill sex drive. Above 5mg/day for extended periods may cause kidney problems. Letrozole has also been shown to delay the fusing of the growth plates in adolescents. This may boost the effectiveness of growth hormone, and thus Letrozole is used to treat adolescents and children with short stature. A triazole and benzonitrile derivative that is a selective non-steroidal aromatase inhibitor, similar to ANASTROZOLE. It is used in the treatment of metastatic or locally advanced breast cancer in postmenopausal women. See also: Letrozole; ribociclib succinate (component of). Letrozole (INN, trade name Femara) is an oral non-steroidal aromatase inhibitor that has been introduced for the adjuvant treatment of hormonally-responsive breast cancer L - Antineoplastic and immunomodulating agents > L02 - Endocrine therapy > L02B - Hormone antagonists and related agents > L02BG - Aromatase inhibitors D006730 - Hormones, Hormone Substitutes, and Hormone Antagonists > D006727 - Hormone Antagonists > D065088 - Steroid Synthesis Inhibitors D006730 - Hormones, Hormone Substitutes, and Hormone Antagonists > D006727 - Hormone Antagonists > D004965 - Estrogen Antagonists C274 - Antineoplastic Agent > C2189 - Signal Transduction Inhibitor > C129824 - Antineoplastic Protein Inhibitor D004791 - Enzyme Inhibitors > D065088 - Steroid Synthesis Inhibitors > D047072 - Aromatase Inhibitors C274 - Antineoplastic Agent > C129818 - Antineoplastic Hormonal/Endocrine Agent > C481 - Antiestrogen C274 - Antineoplastic Agent > C163758 - Targeted Therapy Agent > C1740 - Aromatase Inhibitor C471 - Enzyme Inhibitor > C129825 - Antineoplastic Enzyme Inhibitor C147908 - Hormone Therapy Agent > C547 - Hormone Antagonist D000970 - Antineoplastic Agents CONFIDENCE standard compound; EAWAG_UCHEM_ID 3585 Letrozole (CGS 20267) is a potent, selective, reversible and orally active non-steroidal inhibitor of aromatase, with an IC50 of 11.5 nM. Letrozole selective inhibits estrogen biosynthesis, and can be used for the research of breast cancer[1][2][3].

   
   
   

Letrozole related compound B

Letrozole related compound B

C17H11N5 (285.1014406)


   

Femara

4-[(4-cyanophenyl)-(1,2,4-triazol-1-yl)methyl]benzonitrile

C17H11N5 (285.1014406)


L - Antineoplastic and immunomodulating agents > L02 - Endocrine therapy > L02B - Hormone antagonists and related agents > L02BG - Aromatase inhibitors D006730 - Hormones, Hormone Substitutes, and Hormone Antagonists > D006727 - Hormone Antagonists > D065088 - Steroid Synthesis Inhibitors D006730 - Hormones, Hormone Substitutes, and Hormone Antagonists > D006727 - Hormone Antagonists > D004965 - Estrogen Antagonists C274 - Antineoplastic Agent > C2189 - Signal Transduction Inhibitor > C129824 - Antineoplastic Protein Inhibitor D004791 - Enzyme Inhibitors > D065088 - Steroid Synthesis Inhibitors > D047072 - Aromatase Inhibitors C274 - Antineoplastic Agent > C129818 - Antineoplastic Hormonal/Endocrine Agent > C481 - Antiestrogen C274 - Antineoplastic Agent > C163758 - Targeted Therapy Agent > C1740 - Aromatase Inhibitor C471 - Enzyme Inhibitor > C129825 - Antineoplastic Enzyme Inhibitor C147908 - Hormone Therapy Agent > C547 - Hormone Antagonist D000970 - Antineoplastic Agents Letrozole (CGS 20267) is a potent, selective, reversible and orally active non-steroidal inhibitor of aromatase, with an IC50 of 11.5 nM. Letrozole selective inhibits estrogen biosynthesis, and can be used for the research of breast cancer[1][2][3].