| abstract |
The invention relates to amino acid derivatives of general formula (I), wherein R1 is H or CH3, X is H or NR2R3, wherein R2 is H, CH3, COH or COCH3 and R3 is H, CH3 or COO-Z wherein Z is R2R3 NH+CHR1(CH2)nCOO(CH2)mCH2Y; Y is H, CH3 or NHR4, wherein R4 a COO-NH3+CH2(CH2)mOOC(CH2)nCH3, the meaning of group (CH2)m being selected from alkyls, secondary alkyls, monocycloalkyls, bicycloalkyls and tricycloalkyls having from 4 to 15 carbon atoms and n having a value of from 3 to 14. omega-Amino acid derivatives of the invention are prepared by reacting a primary or secondary or monocyclic or bicyclic or tricyclic alcohol with the reaction product of an amino acid or an N-substituted amino acid with thionyl chloride, whereafter the amino group, which has been released by an amine, reacts with carbon dioxide providing a derivative of carbamic acid, or by directly reacting a primary or secondary or monocyclic or bicyclic or tricyclic alcohol with an N-substituted amino acid in the presence of a condensing agent giving the corresponding ester of the N-substituted amino acid. Thus produced compounds of formula (I) can be used as transdermal penetration enhancers. Incorporation of from 0.1 w/w percent to 5.0 w/w percent of a compound of the invention as a transdermal penetration enhancer in the vehicle of a topically applied pharmaceutical or cosmetic composition enhances transdermal penetration of pharmaceutical agents through the human or animal skin. Included further are transdermal penetration enhancers consisting of at least one compound of formula (I). |