If the concentration of glucose $\left({\mathrm{C}}_6{\mathrm{H}}_{12}{\mathrm{O}}_6\right)$ in blood is 0.72 $\mathrm{g}{ \mathrm{L}}^{-1}$, the molarity of glucose in blood is   _______ $\times {10}^{-3}\mathrm{M}$. [Given : Atomic mass of $\mathrm{C}=12,\mathrm{H}=1,\mathrm{O}=16\mathrm{u}]$