Enzacamene

Enzacamene (INN; also known as 4-methylbenzylidene camphor or 4-MBC) is an organic camphor derivative that is used in the cosmetic industry for its ability to protect the skin against UV, specifically UV B radiation. As such, it is used in sunscreen lotions and other skincare products claiming a SPF value. Its tradenames include Eusolex 6300 (Merck) and Parsol 5000 (DSM).

Enzacamene^[1]

Names
IUPAC name (3E)-1,7,7-Trimethyl-3-[(4-methylphenyl)methylene]-2-norbornanone
Other names 4-Methylbenzylidene camphor 3-(4-Methylbenzylidene)bornan-2-one 3-(4-Methylbenzylidene)-dl-camphor
Identifiers
CAS Number	36861-47-9 Y
3D model (JSmol)	Interactive image
Abbreviations	4-MBC
ChemSpider	4939160 Y
ECHA InfoCard	100.048.386
EC Number	253-242-6
PubChem CID	6434217
UNII	8I3XWY40L9 Y
CompTox Dashboard (EPA)	DTXSID201348972 DTXSID8047896, DTXSID201348972
InChI InChI=1S/C18H22O/c1-12-5-7-13(8-6-12)11-14-15-9-10-18(4,16(14)19)17(15,2)3/h5-8,11,15H,9-10H2,1-4H3/b14-11+ Y Key: HEOCBCNFKCOKBX-SDNWHVSQSA-N Y InChI=1/C18H22O/c1-12-5-7-13(8-6-12)11-14-15-9-10-18(4,16(14)19)17(15,2)3/h5-8,11,15H,9-10H2,1-4H3/b14-11+ Key: HEOCBCNFKCOKBX-SDNWHVSQBW
SMILES O=C2\C(=C\c1ccc(cc1)C)C3CCC2(C)C3(C)C
Properties
Chemical formula	C18H22O
Molar mass	254.37 g/mol
Appearance	White crystalline powder
Melting point	66 to 69 °C (151 to 156 °F; 339 to 342 K)
Solubility in water	Insoluble
Hazards
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H410
Precautionary statements	P273, P391, P501
Pharmacology
Legal status	Banned in Thailand, Palau and Hawaii
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

Mechanism

All the camphor-derived sunscreens dissipate the photon energy by cis-trans isomerisation. However, for enzacamene the quantum yield for this isomerization is only between 0.13-0.3. This low quantum yield means that other photochemical processes are also occurring.^[2]

Endocrine disruptor

Studies have raised the issue that enzacamene acts as an endocrine disruptor. There is controversy about the estrogenic effects of enzacamene and while one study showed only a relatively minor effect.^[3] In addition, there is some evidence that enzacamene may suppress the pituitary-thyroid axis, leading to hypothyroidism.^[4]

Approval status

Enzacamene is approved in Canada by Health Canada. It is not approved for use in the United States by the Food and Drug Administration and it is not permitted in Japan nor in Denmark.^[5]

See also

• Xenoestrogen