Remuneration and interest to partners- under sec. 44ad

Yes, you can do that. But then you have to check whether you had included such interest or remuneration in the partner's personal tax computation. The partners also have to mention particulars about profit share, firm's PAN etc in their personal ITR.

Since you are now filing belated return or of earlier years, it is possible that such interest or remuneration which you now want to deduct from firm's income was not taxed in partner's personal returns. So, it is better to avoid these deductions.