In Acol, if 1444, then pd should open 1D. So opening 1C and raise to 2D should show a 5431 or 5422 hand. Without much discussion, 3N is probably practical choice. However, if pd has sth like: S: x H: XXX D: KQXX C: AKQXX you may miss a slam. I think i will try 2S, if pd can bid 2N, showing stopper in H, then I will raise to 3N. Slam is unlikely if pd has high card in heart suit. If pd retreat to 3C or 3D,denying H card. I will raise to 4D if it is forcing. Otherwise, i will try 6D.