  We study intersection matrix algebras im(A^d) that arise from affinizing a
Cartan matrix A of type B_r with d arbitrary long roots in the root system
$\Delta_{B_r}$, where $r \geq 3$. We show that im(A^d) is isomorphic to the
universal covering algebra of $so_{2r+1}(a,\eta,C,\chi)$, where $a$ is an
associative algebra with involution $\eta$, and $C$ is an $a$-module with
hermitian form $\chi$. We provide a description of all four of the components
$a$, $\eta$, $C$, and $\chi$.
