2-Methoxyestradiol

2-Methoxyestradiol
Clinical data
Trade names	Panzem
Other names	2-ME2; 2-MeO-E2; 2-MeOE2; 2-Hydroxyestradiol 2-methyl ether; 2-Methoxyestra-1,3,5(10)-triene-3,17β-diol
Identifiers
	IUPAC name (8R,9S,13S,14S,17S)-2-Methoxy-13-methyl-6,7,8,9,11,12,14,15,16,17-decahydrocyclopenta[a]phenanthrene-3,17-diol;
CAS Number	362-07-2 ;
PubChem CID	66414;
ChemSpider	59788 ;
UNII	6I2QW73SR5;
ChEBI	CHEBI:28955 ;
ChEMBL	ChEMBL299613 ;
CompTox Dashboard (EPA)	DTXSID3040938 ;
ECHA InfoCard	100.164.606
Chemical and physical data
Formula	C19H26O3
Molar mass	302.414 g·mol−1
3D model (JSmol)	Interactive image;
	SMILES Oc1cc3c(cc1OC)[C@H]2CC[C@@]4([C@@H](O)CC[C@H]4[C@@H]2CC3)C;
	InChI InChI=1S/C19H26O3/c1-19-8-7-12-13(15(19)5-6-18(19)21)4-3-11-9-16(20)17(22-2)10-14(11)12/h9-10,12-13,15,18,20-21H,3-8H2,1-2H3/t12-,13+,15-,18-,19-/m0/s1 ; Key:CQOQDQWUFQDJMK-SSTWWWIQSA-N ;
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2-Methoxyestradiol (2-ME2, 2-MeO-E2) is a natural metabolite of estradiol and 2-hydroxyestradiol (2-OHE2). It is specifically the 2-methyl ether of 2-hydroxyestradiol. 2-Methoxyestradiol prevents the formation of new blood vessels that tumors need in order to grow (angiogenesis), hence it is an angiogenesis inhibitor. It also acts as a vasodilator and induces apoptosis in some cancer cell lines. 2-Methoxyestradiol is derived from estradiol, although it interacts poorly with the estrogen receptors (2,000-fold lower activational potency relative to estradiol). However, it retains activity as a high-affinity agonist of the G protein-coupled estrogen receptor (GPER) (10 nM, relative to 3–6 nM for estradiol).

Selected biological properties of endogenous estrogens in rats
Estrogen	ERTooltip Estrogen receptor RBATooltip relative binding affinity (%)	Uterine weight (%)	Uterotrophy	LHTooltip Luteinizing hormone levels (%)	SHBGTooltip Sex hormone-binding globulin RBATooltip relative binding affinity (%)
Control	–	100	–	100	–
Estradiol (E2)	100	506 ± 20	+++	12–19	100
Estrone (E1)	11 ± 8	490 ± 22	+++	?	20
Estriol (E3)	10 ± 4	468 ± 30	+++	8–18	3
Estetrol (E4)	0.5 ± 0.2	?	Inactive	?	1
17α-Estradiol	4.2 ± 0.8	?	?	?	?
2-Hydroxyestradiol	24 ± 7	285 ± 8	+^b	31–61	28
2-Methoxyestradiol	0.05 ± 0.04	101	Inactive	?	130
4-Hydroxyestradiol	45 ± 12	?	?	?	?
4-Methoxyestradiol	1.3 ± 0.2	260	++	?	9
4-Fluoroestradiol^a	180 ± 43	?	+++	?	?
2-Hydroxyestrone	1.9 ± 0.8	130 ± 9	Inactive	110–142	8
2-Methoxyestrone	0.01 ± 0.00	103 ± 7	Inactive	95–100	120
4-Hydroxyestrone	11 ± 4	351	++	21–50	35
4-Methoxyestrone	0.13 ± 0.04	338	++	65–92	12
16α-Hydroxyestrone	2.8 ± 1.0	552 ± 42	+++	7–24	<0.5
2-Hydroxyestriol	0.9 ± 0.3	302	+^b	?	?
2-Methoxyestriol	0.01 ± 0.00	?	Inactive	?	4
Notes: Values are mean ± SD or range. ER RBA = Relative binding affinity to estrogen receptors of rat uterine cytosol. Uterine weight = Percentage change in uterine wet weight of ovariectomized rats after 72 hours with continuous administration of 1 μg/hour via subcutaneously implanted osmotic pumps. LH levels = Luteinizing hormone levels relative to baseline of ovariectomized rats after 24 to 72 hours of continuous administration via subcutaneous implant. Footnotes: ^a = Synthetic (i.e., not endogenous). ^b = Atypical uterotrophic effect which plateaus within 48 hours (estradiol's uterotrophy continues linearly up to 72 hours). Sources: See template.