Embedding of the Lie superalgebra D(2,1;α) into the Lie superalgebra of pseudodifferential symbols on S1|2

We obtain an embedding of the one-parameter family of exceptional simple Lie superalgebras D(2,1;α) into the Lie superalgebra of pseudodifferential symbols on the supercircle S1verticalbar2. Correspondingly, there is an embedding of D(2,1;α) into a nontrivial central extension of the derived contact superconformal algebra K'(4) realized in terms of 4x4 matrices over a Weyl algebra