3-(ethoxycarbonyl)-1-(4-ethoxyphenyl)-4,5-dihydro-1H-pyrazole-5-carboxylic acid

4-(3,5-dinitrobenzoyl)-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(naphthalene-2-carbonyl)-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(3-methoxybenzoyl)-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(3,4-difluorobenzoyl)-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(4-methoxybenzoyl)-8-methyl-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-[2-(4-methoxyphenyl)acetyl]-8-methyl-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(3-fluorobenzoyl)-8-methyl-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(3-chlorobenzoyl)-8-methyl-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-(2-chloro-5-nitrobenzoyl)-8-methyl-1-oxa-4-azaspiro[4.5]decane-3-carboxylic acid

4-benzoyl-8-methyl-1-oxa-4,8-diazaspiro[4.5]decane-3-carboxylic acid