The invention provides compounds of Formula I, stereoisomers or pharmaceutically acceptable salts thereof, wherein A, B, D, R
1
, R
2
, R
4
and R
5
are defined herein, a pharmaceutical composition that includes a compound of Formula I and methods of use thereof
Two novel general experimental procedures for preparation of neutral monomethine cyanine dyes without using a basic agent have been developed. The procedures allow synthesis of cyanine dyes by reaction of substituted methylthio aromatic heterocycles with different quaternized nitrogen containing heterocycles by simple melting or by their reaction in acetic anhydride for short reaction times. The proposed
A compound represented by the formula (I): wherein each symbol is as defined in the specification, and a salt thereof have a GPR40 receptor activation action and is useful as an insulin secretagogue or a prophylactic or therapeutic drug for diabetes and the like.