Abstract: Compounds are disclosed having the structure of Formula I: where R1 , R3, and R4 are independently hydrogen or C1 to C4 alkyl, and R2 is: where R5 is selected from the group consisting of hydrogen and C1 to C4 alkyl, or where R6, R7 and R8 are independently hydrogen or C1 to C4 alkyl; or the esters or pharmacologically acceptable salts thereof. Such compounds may be utilized for the prophylaxis or treatment of various diseases, particularly inflammatory conditions of the GI tract. Methods of treating inflammatory conditions of the GI tract such as inflammatory bowel disease using compounds having the following formula are also disclosed: where R9, R10 and R11 are independently selected from the group consisting of hydrogen and C1 to C4 alkyl, and R12 is selected from the group consisting of hydrogen and —C(O)R13, where R13 is a C1 to C6 alkyl or an aryl group.