Novel CFTR corrector compounds that are effective in rescuing halide efflux, delF508-CFTR protein processing, and apical functional chloride ion transport in a cell are provided. Also provided are methods for treating protein folding disorders (e.g., cystic fibrosis and chronic obstructive pulmonary diseases). The methods include administering a CFTR corrector compound or pharmaceutically acceptable salt or prodrug thereof. Methods of rescuing halide efflux in a cell, correcting a processing defect of a delF508-CFTR protein in a cell, and correcting functional delF508-CFTR chloride channels in a cell are also provided.