One‐Pot Synthesis of Diazine‐Bridged Bisindoles and Concise Synthesis of the Marine Alkaloid Hyrtinadine A

Abstract

Keywords: Alkaloids / Arylation / Boron / C-C coupling / Multicomponent reactions / Palladium Diazine-bridged bisindoles are readily obtained from N-Bocprotected 3-iodoindoles and 3-iodo-7-azaindole in a pseudo three-component reaction involving a one-pot Masuda borylation-Suzuki arylation sequence. Some of the title com-

Marine Bi-, Bis-, and Trisindole Alkaloids

“…82 Compound 152 was also found to be cytotoxic in HCT116 colon carcinoma and A2780 ovarian carcinoma cell lines with IC 50 values of 3.7 and 4.5 mM, respectively. 83 Hyrtinadine A did not inhibit kinase activity when screened against 110 different kinase enzymes. 83 …”

“…83 Hyrtinadine A did not inhibit kinase activity when screened against 110 different kinase enzymes. 83 …”

“…Demethylation of 157 with BBr 3 delivered hyrtinadine A. 83 This method was used to synthesize a number of analogs and regioisomers of 152 suitable for structure activity relationship studies. 83 …”

Racemosins A and B, two novel bisindole alkaloids from the green alga Caulerpa racemosa

“…In addition, some of these marine bisindole compounds were found to be responsible for potent and diverse bioactive properties, e.g., antifungal [8,10], antibacterial [11], antiviral [12], cytotoxic [7], anti-inflammatory [13], and noteworthy antitumor [12,14] activities. Their excellent bioactivities have for a long time attracted great interest from (bio)synthetic organic chemists as challenging targets for total synthesis as well as biosynthetic studies [15][16][17][18]. Up to now, more than 120 naturally occuring or chemo(bio)syhthetic marine bisindole alkaloids have been discovered, and some of them possessed new carbon skeletons.…”

Palladium‐Catalyzed Oxidative Carbocyclization–Borylation of Enallenes to Cyclobutenes

“…[5][6][7][8][9][10][11][12] During these studies, we observed that formation of cyclobutene 2,presumably via intermediate Int-2,w as highly favored under certain conditions (Scheme 1b). [5][6][7][8][9][10][11][12] During these studies, we observed that formation of cyclobutene 2,presumably via intermediate Int-2,w as highly favored under certain conditions (Scheme 1b).…”