The present invention relates to a functionalized siloxy compound which is useful in silica-filled rubber compositions and the processing of a sulfur curable rubber composition containing silica. Accordingly, the invention further relates to a rubber composition containing at least one diene-based elastomer, particulate synthetic amorphous silica (e.g. precipitated silica) and said functionalized siloxy compound as a coupling agent and to an article of manufacture (e.g. tire) containing a component comprised of such rubber composition.