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@article{210906,
        author = {Aakib Hushen and Raj Kumar},
        title = {Two Pharmacophores, One Labile Bond: 1,3,4-Oxadiazole–Schiff Base Hybrids},
        journal = {International Journal of Innovative Research in Technology},
        year = {2026},
        volume = {13},
        number = {6},
        pages = {2819-2830},
        issn = {2349-6002},
        url = {https://ijirt.org/article?manuscript=210906},
        abstract = {The 1,3,4-oxadiazole ring earns its place in medicinal chemistry for one reason above others: it is a hydrolytically stable bioisostere of the ester and the amide, and that stability is why it appears in raltegravir, zibotentan, tiodazosin and furamizole. The Schiff base contributes the opposite property. Its azomethine C=N bond is formed by a reversible, thermodynamically controlled condensation that is driven forward only by removal of water, and it is cleaved back to aldehyde and amine by the reverse reaction, rapidly below about pH 4 and more slowly within the pH 6 to 10 window where such compounds are described as stable. Joining the two through that bond therefore produces a hybrid in which a deliberately robust fragment is attached to a deliberately labile one, and the consequence for in vitro screening is specific and underexamined. The albumin-denaturation assay that supplies most published anti-inflammatory data for these compounds is run in buffer adjusted to pH 6.4 with glacial acetic acid and heated to 72 °C; it is a physicochemical measurement of resistance to heat-induced protein aggregation rather than a measurement of any inflammatory mechanism, and neither hydrolysis product of a typical hybrid is pharmacologically silent in it. Phenolic and other substituted aromatic aldehydes are active in the same assay in their own right. No hybrid study located for this review reports a stability control under its own assay conditions, and very few report the two parent fragments alongside the hybrid the comparison on which the word hybridization actually depends. This review sets out the synthetic routes to the core and to the hybrid, the characterisation that confirms each bond, what the reported cyclooxygenase data support, and the small set of controls that would convert a plausible design narrative into a demonstrated one.},
        keywords = {1,3,4-Oxadiazole; Schiff base; azomethine; molecular hybridization; anti-inflammatory; cyclooxygenase; protein denaturation assay; hydrolytic stability},
        month = {November},
        }