Is it permissible to refrain from benefiting from land that is encumbered with debt, and does the sin fall upon the brothers or upon the deceased father?

Paying the debt of the deceased takes precedence over distributing their inheritance. The rights related to the inheritance are prioritized as follows: preparing and shrouding the deceased, then paying off their debts, then executing their bequests, and the remainder goes to the heirs. It is not permissible for the heirs to divide an inheritance burdened with debt, because their ownership does not become apparent until after the debt is paid. If the questioner refuses what the inherited land produces to compel the remaining heirs to pay the debt, that is correct. As for the responsibility for the debt, it rests with the deceased as long as they left enough to fulfill their debt, and the heirs are sinful if they divide the inheritance without settling the debt. There is a disagreement about whether a deferred debt becomes due upon death or not, and the majority of scholars believe it is obligatory to expedite its payment just like a current debt. The questioner is advised to refer the matter to the Sharia court to compel the heirs to pay the debt.