Octylmethoxy cinnamate, also known as octinoxate or Ethylhexyl methoxycinnamate, is an organic compound commonly used in sunscreens and cosmetic products as a UVB (ultraviolet B) filter. It is a clear, oily liquid that is insoluble in water but soluble in organic solvents.

Octylmethoxy cinnamate works by absorbing and filtering UVB radiation, which is responsible for sunburn and contributes to the development of skin cancer. It helps protect the skin from the harmful effects of the sun's UV rays.

This compound is approved by regulatory agencies, such as the U.S. Food and Drug Administration (FDA), for use in sunscreens at concentrations up to 7.5%. It is often combined with other sunscreen ingredients, such as avobenzone or titanium dioxide, to provide broad-spectrum protection against both UVB and UVA (ultraviolet A) rays.

It's important to note that while octylmethoxy cinnamate is widely used and considered safe in approved concentrations, some individuals may have sensitivities or allergies to this ingredient. If you have any concerns or experience skin reactions, it's advisable to consult with a dermatologist or healthcare professional.