Polyphenylene ether derivatives having a N- substituted maleimide group, and the thermosetting resin composition using the same, a resin varnish, a prepreg, metal clad laminated board and multilayer printed wiring board

The N- substituted maleimide represented by the following formula (I), polyphenylene ether derivative having at least a one in the molecule, and the thermosetting resin composition using the same, prepreg, metal-clad laminate, and multi-layer a printed wiring board. (In the formula, R