クロモノ[3,4-]インドリジン誘導体2種の結晶構造解析：コンフォメーションと超分子構造の特徴
Two spiro-fused chromeno[3,4-]indolizine compounds bearing 4-chlorophenyl (I) and 4-methoxyphenyl (II) substituents were characterized by X-ray crystallography. The six-membered pyran and piperidine rings adopt envelope and chair conformations, respectively, while the five-membered pyrrolidine rings display twist conformations. Compound II contains two crystallographically independent molecules in the asymmetric unit. An intramolecular C–H···O hydrogen bond forming a seven-membered ring motif is present in all three molecular entities. Disorder was observed in the nitro group of I and in the methoxybenzene moiety of one molecule of II. Intermolecular C–H···O and C–H···Cl contacts in I generate chains along [010] that further assemble into layers, while C–H···π interactions reinforce the packing. In II, C–H···O bonds connect the two independent molecules into square four-membered units, which are further organized into a three-dimensional supramolecular framework through multiple C–H···π contacts.
The delivery route is not clearly identifiable from this paper. For hydrogen intake, inhalation is the most efficient route; inhalation, however, carries explosion risk (empirical LFL of 10%; high-concentration devices are not recommended).
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https://h2-papers.org/en/papers/30800454