Step-economic synthesis of (±)-debromoflustramine A using indole C3 activation strategy

Regioselective Cope Rearrangement and Prenyl Transfers on Indole Scaffold Mimicking Fungal and Bacterial Dimethylallyltryptophan Synthases

“…As shown in Table , in order to test the feasibility of a [3,3]-sigmatropic rearrangement on the open-chain indole scaffold, we prepared a variety of substrates using a Meerwein–Eschenmoser–Claisen rearrangement − on C3-substituted indoles ( 15 ). Treatment of nitrile-containing C3-substituted indole 15a with N -chlorosuccinimide (NCS) in the presence of 1,4-dimethylpiperazine, prenol ( 8 ), and trichloroacetic acid resulted in a 61% yield of oxindole 16a .…”

Pd/Cu Cocatalyzed Oxidative Tandem C–H Aminocarbonylation and Dehydrogenation of Tryptamines: Synthesis of Carbolinones

“…The title compound was isolated as a light yellow solid (366 mg, 32% yield). 22 7.6 Hz, 1H), 7.20 (dd, J = 8.0, 7.2 Hz, 1H), 7.12 (dd, J = 7.6, 7.2 Hz,1H), 7.05 (s, 1H), 3.03−2.94 (m, 4H), 2.82 (hept, J = 6.4 Hz, 1H), 1.06 (d, J = 6.4 Hz, 6H); 13 C{ 1 H} NMR (100 MHz, CDCl 3 ) δ 136. 3, 127.3, 122.0, 119.2, 118.9, 113.9, 111.1, 48.6, 47.3, 25.8, 22.8 N-(Phenylmethyl)-1H-indole-3-ethanamine 1e.…”

Simple indole alkaloids and those with a non-rearranged monoterpenoid unit

“…The key conjugative step involved an NCSmediated activation of tryptophan, followed by trapping the indolenine intermediate with prenyl alcohol resulting in the reverse-prenylated oxindole via Eschenmoser-Claisen rearrangement (Scheme 86). 150 The rst total synthesis of dimeric tryptophan alkaloid, okaramine M (305), was achieved through the Ugi threecomponent reaction of imine, p-methoxyphenyl isonitrile (PMP-NC), and N-Boc-L-tryptophan. The proposed structure of okaramine M was revised on the basis of the synthetic evidence (Scheme 87).…”