Streamlined modular synthesis of saframycin substructure via copper-catalyzed three-component assembly and gold-promoted 6-endo cyclization

• Asahi Kanno,
• Ryo Tanifuji,
• Satoshi Yoshida,
• Sota Sato,
• Saori Maki-Yonekura,
• Kiyofumi Takaba,
• Jungmin Kang,
• Kensuke Tono,
• Koji Yonekura and
• Hiroki Oguri

Beilstein J. Org. Chem. 2025, 21, 226–233, doi:10.3762/bjoc.21.14

• involvement of a fluorescent intermediate in the cascade synthetic process. Keywords: cascade reactions; copper-catalyzed three-component coupling; gold-mediated 6-endo hydroamination; tandem cyclizations; tetrahydroisoquinoline alkaloids; Introduction The bis-tetrahydroisoquinoline (THIQ) alkaloid family

The ethoxycarbonyl group as both activating and protective group in N-acyl-Pictet–Spengler reactions using methoxystyrenes. A short approach to racemic 1-benzyltetrahydroisoquinoline alkaloids

• Marco Keller,
• Karl Sauvageot-Witzku,
• Franz Geisslinger,
• Nicole Urban,
• Michael Schaefer,
• Karin Bartel and
• Franz Bracher

Beilstein J. Org. Chem. 2021, 17, 2716–2725, doi:10.3762/bjoc.17.183

• approaches to the monomeric 1-benzyl-1,2,3,4-tetrahydroisoquinoline alkaloids are typically inspired by their biosynthesis and comprise Bischler–Napieralski-type cyclizations of arylacetamides (followed by reduction of the resulting 3,4-dihydroisoquinolines) or Pictet–Spengler-type cyclizations of

• -tetrahydroisoquinoline alkaloids (Figure 2 and Table 1). Since, as mentioned above, we recently demonstrated that substituted 1-benzyl-1,2,3,4-tetrahydroisoquinolines exhibit both cytotoxic and calcium channel-modulating activities, we subjected these alkaloids to our established screening systems in order to gain new

• ” retained antiproliferative activity, while losing activity on TPC2 [15]. This prompted us to analyze both TPC2 modulating and antiproliferative activities of the alkaloids from this project. TPC2 modulation To assess the activity of racemic 1-benzyl-1,2,3,4-tetrahydroisoquinoline alkaloids on TPC2 in

β-Hydroxy sulfides and their syntheses

• Mokgethwa B. Marakalala,
• Edwin M. Mmutlane and
• Henok H. Kinfe

Beilstein J. Org. Chem. 2018, 14, 1668–1692, doi:10.3762/bjoc.14.143

• architectural extreme are: the ecteinascidins, antitumor tetrahydroisoquinoline alkaloids from the colonial Ascidian Ecteinascidia turbinata as exemplified by ecteinascidin 729 (4) [6]; ulbactins F (5a) and G (5b), two polycyclic thiazoline congeners isolated from a culture extract of a sponge derived