  Energy levels, hyperfine interaction constants, and Land\'e $g_J$-factors are
reported for n=2 states in beryllium-, boron-, carbon-, and nitrogen-like ions
from relativistic configuration interaction calculations. Valence,
core-valence, and core-core correlation effects are taken into account through
single and double-excitations from multireference expansions to increasing sets
of active orbitals. A systematic comparison of the calculated hyperfine
interaction constants is made with values from the available literature.
