Obacunone, a natural product isolated and purified from the barks of Phellodendron chinense, has cytotoxicity in androgen-dependent human prostate cancer cells. Obacunone may have the potential to prevent estrogen-responsive breast cancer through inhibition of the aromatase enzyme and inflammatory pathways, as well as activation of apoptosis.

Fadrozole is a selective aromatase inhibitor that has been introduced in Japan for the treatment of breast cancer.

Fadrozole HCl specifically inhibits aromatase, blocking the aromatization of androstenedione and testosterone into estrone and estradiol, respectively.

Endoxifen is a key active metabolite of tamoxifen (TAM) with higher affinity and specificity to estrogen receptor that also inhibits aromatase activity.

Chrysin, an analog of apigenin, demonstrates inhibition of aromatase and the phosphorylation of PLCY2 and PKC activities. It can be isolated from the blue passion flower (passiflora caerulea) with anti-inflammatory and anti-thrombotic activities etc..

Urolithin B is a natural product with anti-proliferative and antioxidant activity, which can penetrate the blood-brain barrier and may have neuroprotective effects against Alzheimer’s Disease.It inhibits aromatase activity in human placental microsomes and aromatase-sensitive MCF-7 (MCF-7aro) human breast cancer cells when used at concentrations of 47 and 4.7 µM, respectively.

YM 511 is an orally active, potent aromatase (CYP19) inhibitor with IC50 of 0.4 and 0.12 nM at rat ovary and human placenta cells respectively.