5-Acyl-5-phenyl-1,5-dihydro-4H-pyrazol-4-ones, accessible from arylpropargyl phenyldiazoacetates, are highly selective acyl transfer reagents for di- and polyamines, as well as aminoalcohols and aminothiols. As reagents with a carbon-based leaving group, they have been applied for benzoyl transfer with a broad selection of substrates containing aliphatic amino in combination with other competing nucleophilic functional groups. The substrate scope and levels of selectivity for direct benzoyl transfer exceed those of known benzoylating reagents. With exceptional selectivity for acylation between primary amines bound to primary and secondary carbons, these new reagents have been used in direct site-selective monobenzoylation of aminoglycoside antibiotics.

中文翻译：

---

5-酰基-5-苯基-1,5-二氢-4 H-吡唑-4-酮对多胺和氨基糖苷的高度选择性酰化

可从芳基炔丙基苯基重氮乙酸酯获得的5-酰基-5-苯基-1，5-二氢-4 H-吡唑-4-酮是对二胺和多胺以及氨基醇和氨基硫醇的高度选择性的酰基转移试剂。作为具有碳基离去基团的试剂，它们已用于苯甲酰转移，可广泛选择包含脂肪族氨基与其他竞争性亲核官能团的底物。直接苯甲酰基转移的底物范围和选择性水平超过了已知的苯甲酰化试剂的范围和水平。这些新试剂对与伯碳和仲碳键合的伯胺之间的酰化反应具有出色的选择性，已被用于氨基糖苷类抗生素的直接位点选择性单苯甲酰化。