Toluene → Boc Cyclopropyl Tryptophan p-Nitrobenzyl Ester

Beteiligte Stoffe

Reaktionsschritte

The pyrazoline, p-nitrobenzyl 3-t-butoxycarbonylamino-5-(N-tosylindol-3-yl)-pyrazoline-3-carboxylate (13), (1 mmole) is suspended in toluene (50 ml) and the mixture is refluxed until its NMR spectrum shows the presence of cyclopropane protons (δ3.0-3.5 and 0.8-1.2 ppm) and the loss of the pyrazoline peak at δ5.0. (2 hr). The solution is evaporated and the residue of Boc cyclopropyl tryptophan p-nitrobenzyl ester (14) is crystallized from ethylacetate-hexane. NMR (DCDl3)δ: 2.7-3.0 (m, 1H, CH), 2.0-2.3 and 1.5-1.7 (m, 2H, CH2).

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