Drometrizole trisiloxane (INCI) is a lipophilic benzotriazole derivative marketed as Mexoryl XL by L'Oréal and is used in sunscreens to absorb UV radiation. It is a broad-spectrum UV absorber with two absorption peaks, one at 303 nm (UVB) and one at 344 nm (UVA). Just like Mexoryl SX (ecamsule), it is used exclusively in products by L'Oréal owned brands. Drometrizole trisiloxane and ecamsule are often used together, because they show a synergistic effect in protection.^[1]

Quick Facts Names, Identifiers ...

Drometrizole trisiloxane

Names
Preferred IUPAC name 2-(2H-Benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-[1,3,3,3-tetramethyl-1-[(trimethylsilyl)oxy]-1-disiloxanyl]propyl]phenol
Systematic IUPAC name 2-(2H-1,2,3-Benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-(2,2,4,6,6-pentamethyl-3,5-dioxa-2,4,6-trisilaheptan-4-yl)propyl]phenol
Other names 2-(1,2,3-Benzotriazol-2-yl)-4-methyl-6-[2-methyl-3-(2,2,4,6,6-pentamethyl-3,5-dioxa-2,4,6-trisilaheptan-4-yl)propyl]phenol Silatrizole
Identifiers
CAS Number	155633-54-8 N
3D model (JSmol)	Interactive image Interactive image
ChemSpider	8024601 Y
ECHA InfoCard	100.121.988
PubChem CID	9848888
UNII	HC22845I1X Y
CompTox Dashboard (EPA)	DTXSID40431753
InChI InChI=1S/C24H39N3O3Si3/c1-18-14-20(15-19(2)17-33(9,29-31(3,4)5)30-32(6,7)8)24(28)23(16-18)27-25-21-12-10-11-13-22(21)26-27/h10-14,16,19,28H,15,17H2,1-9H3 Key: HUVYTMDMDZRHBN-UHFFFAOYSA-N
SMILES CC(CC1=C(O)C(=CC(C)=C1)N1N=C2C=CC=CC2=N1)C[Si](C)(O[Si](C)(C)C)O[Si](C)(C)C CC1=CC(N3N=C2C=CC=CC2=N3)=C(O)C(CC(C)C[Si](O[Si](C)(C)C)(O[Si](C)(C)C)C)=C1
Properties
Chemical formula	C24H39N3O3Si3
Molar mass	501.849 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Close

Sunscreens with drometrizole trisiloxane are approved within the EU,^[2] Canada,^[3] Australia,^[4] Japan,^[5] and other countries, but not in the United States.