Shet, S.N.Bhat, V.G.Swathi, S.G.Udayakumar, U.Shetti, V.S.2026-02-032025RSC Advances, 2025, 15, 34, pp. 28240-28247https://doi.org/10.1039/d5ra03790ehttps://idr.nitk.ac.in/handle/123456789/20141Azobenzenes (Ph-N = N-Ph) are well-known photochromic compounds with widespread applications. Replacing one or both phenyl rings of azobenzenes with heteroarenes leads to a new class of compounds known as azoheteroarenes (Het-N N-Ph/Het). Azoheteroarenes have gained attention as promising alternatives to traditional azobenzenes in the field of photopharmacology due to their ability to undergo photoswitching under visible light. Interestingly, the chemistry of porphyrin-containing azoheteroarenes has been underexplored. In this study, we present the synthesis of hitherto unknown hybrid molecules: porphyrin-azopyrroles (porphyrin-N N-pyrrole) and porphyrin-azoindoles (porphyrin-N N-indole), which also feature porphyrins with five-membered meso-substituents, such as 2-furyl and 2-thienyl groups. The porphyrin-azoheteroarenes with meso-tris(2-furyl/2-thienyl) substitutions demonstrate red-shifted absorption and emission bands, more significant Stokes shifts, and smaller optical bandgaps compared to hybrids containing only meso-aryl groups. Additionally, these porphyrin-azoheteroarenes exhibit higher fluorescence emission intensities than their corresponding precursor porphyrins. © 2025 The Royal Society of Chemistry.Medicinal chemistryPhotochromismPolycyclic aromatic hydrocarbonsRed ShiftSynthesis (chemical)Computational studiesHeteroarenesHybrid moleculesPhenyl ringsPhotochromic compoundPhotophysical studiesPhotoswitchingRed-shiftedThienylVisible lightAzobenzenePorphyrins