A self-timed memory array is disclosed, in which segmentability and metal-programmability are supported while minimizing layout space. With such structure, temperature characteristics of a phase difference can be obtained so as to reduce a temperature change of an oscillated wavelength emitted from a semiconductor laser source whereby the phase difference can be kept constant even when there is a fluctuation in a wavelength of light emitted from the semiconductor laser source due to temperature. The present invention also relates to processes for the preparation of the compounds of formula, novel intermediates, processes for their preparation, their use in the preparation of the above said compounds and their use as antidiabetic, hypolipidemic, antiobesity and hypocholesterolemic compounds.