Diastereoselective Synthesis of Structurally and Stereochemically Diversified 2‑Oxa-7-azabicyclo[4.1.0]hept-3-enyl Carboxylates and Their Potential Application toward the Synthesis of Functionalized Pyranooxazolone and Pyrrole Derivatives through Skeletal Transformations

An advanced protocol
for the diastereoselective intramolecular
aziridination reaction has been developed to synthesize 2-oxa-7-azabicyclo­[4.1.0]­hept-3-en-1-yl
carboxylates from their corresponding 4-H-pyrans
and spiropyrans analogues employing iodosyl­benznene as the exclusive
oxidant in the presence of carboxylic acid and triethylamine. High
structural and stereochemical diversity of these pyran fused NH-azridine
scaffolds makes them useful in evaluating their biological and pharmacological
activities by SAR studies. Additionally, their potential synthetic
application has been uncovered by efficient transformation into biologically
relevant novel pyrano­oxazolone and pyrrole derivatives.

本研究开发了一种用于非对映选择性分子内氮丙啶化反应的先进合成方案，以亚碘酰苯作为唯一氧化剂，在羧酸与三乙胺共存条件下，由相应的4H-吡喃及螺吡喃类似物合成2-氧杂-7-氮杂双环[4.1.0]庚-3-烯-1-基羧酸酯。此类吡喃稠合NH-氮丙啶骨架具有丰富的结构与立体化学多样性，可通过构效关系（Structure-Activity Relationship, SAR）研究评估其生物与药理活性。此外，通过将该类骨架高效转化为具有生物相关性的新型吡喃并恶唑酮与吡咯衍生物，其潜在的合成应用价值得以发掘。