The DOSERIAL* directive disables parallelization the specified nest of loops. This directive applies to the whole nest of loops immediately following it (if you compile with -explicitpar or -parallel).
Example: Exclude a whole nest of loops from parallelization:
do i = 1, n
C$PAR DOSERIAL*
do j = 1, n
do k = 1, n
...
end do
end do
end do
In the preceding loops, the j and k loops are not parallelized; the i loop could be.