13-hydroxylupanine + (2E)-2-methylbut-2-enoyl-CoA => 13-(2-methylcrotonoyloxy)lupanine + CoA
13-hydroxylupanine + (2e)-2-methylbut-2-enoyl-coa => 13-(2-methylcrotonoyloxy)lupanine + coa
13-hydroxylupanine + (2E)-2-methylbut-2-enoyl-CoA => 13-(2-methylcrotonoyloxy)lupanine + CoA
13-hydroxylupanine + (2e)-2-methylbut-2-enoyl-coa => 13-(2-methylcrotonoyloxy)lupanine + coa