Metal-organic　frameworks　(MOFs)　composed　of　infinite　metal　units　exhibit　enhanced　electron　transport　and　charge　migration　capabilities　compared　to　discrete　metal　units.　Herein,　three　underdeveloped　isomorphic　MOFs　featuring　3D　infinite　zinc　units　are　designed　and　synthesized.　The　Lewis　acidity　and　photocatalytic　activity　of　these　MOFs　are　fine-tuned　through　atomic-level　engineering　of　nitrogen　atoms　of　ligands　and　the　resultant　change　of　charge　transfer　modes.　These　MOFs　are　promising　catalysts　in　the　photocatalytic　monooxygenation　of　sulfenamides　with　molecular　oxygen.　Mechanistic　investigations　suggest　that　the　uneven　charge　distribution　and　large　dipole　moment　at　the　pyridine　center　of　1-PTB　and　the　infinite　Zn　unit　frameworks　of　degenerate　energy　levels　are　key　to　its　excellent　photocatalytic　activity.