Ultra-violet filtration with certain aminosalicylic acid esters
US4036951A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1976 |
| Grant date | Jul 19, 1977 |
| Priority date | — |
| Expiry date | Jan 16, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S424/13
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
Alkyl esters of aminosalicylic acid, said alkyl group having from 1 to 18 carbon atoms in chain length; alkenyl esters of aminosalicylic acid, said alkenyl group selected from the group consisting of vinyl, allyl, undecenyl, oleyl and linolenyl groups, and cyclic esters of aminosalicylic acid, said cyclic group being the cyclohexyl, phenyl and menthyl groups, having ultra-violet screening properties to absorb light rays within the wave-length range of 2950 A. to 3200 A. while transmitting the light rays beyond the 3200 A. range to permit the desirable tanning of the skin without solar burn. The respective esters of aminosalicylic acid are prepared by the reduction of the appropriate nitro-salicylic acid ester with Raney nickel and hydrogen in the presence of ethyl acetate. The respective esters are obtained as oils or solid crystalline substances and are soluble in alcohols, chloroform, acetone and benzene but insoluble in water. The ultra-violet absorption spectra for the respective compounds are described. Compositions comprising the above compounds together with the method for their preparation and the method for the use to achieve an ultraviolet filtering action on the skin of …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.