Bioisosterism is a strategy of Medicinal Chemistry for the rational design of new drugs (bioisosterism is also known as quantum similarity). The success of this strategy in developing new substances which are therapeutically attractive has observed a significant growth in distinct therapeutic classes, being amply used by the pharmaceutical industry to discover new analogs of therapeutic innovations commercially attractive, and also as a tool useful in the molecular modification. In this work,the concept of quantum similarity in the signed particle formulation of quantum mechanics is introduced. This concept was suggested very recently and was studied for the particular case n=1. Therefore, we extend the mathematical expression of similarity to the case n>1, with particular attention to the differences brought in this new context.