you had an extra space: “- nii” instead of “–nii”
also make sure the command is all in one line with no returns.
/Applications/BrainSuite16a1/bdp/bdp.sh /Users/leonidastra86/Desktop/Diffusion/ o20170124_183359lalalas008a1001.bfc.nii –nii /Users/leonidastra86/Desktop/Diffusion/lalala.nii -g /Users/leonidastra86/Desktop/Diffusion/lalala.bvec -b /Users/leonidastra86/Desktop/Diffusion/lalala.bval