Synthesis of Substituted Tropones and Advancement for the Construction of Structurally Significant Skeletons

Abstract

Figure 4. Some examples of norditerpene tropones.

Preparation of Dibenzofurotropones via Pd-Catalyzed Cyclization

“…Tropones, a class of non-benzenoid aromatic compounds, have been found in numerous natural products, showing distinct biological activities [1][2][3][4][5]. Aryl-annulated tropone derivatives such as benzotropones [6][7][8][9][10][11][12][13][14][15][16][17] and furotropones [18][19][20][21][22][23] are also attractive molecules because their extended conjugations might exhibit intriguing chemical and photophysical properties (Figure 1A).…”

“…Pd(OAc)2/PCy3•HBF4 Cs2CO3 (1.2) toluene 110 °C/20 h - 1 Reaction conditions: A mixture of 2aa (0.2 mmol), [Pd] (10 mol%), ligand (20 mol%) and base solvent (2 mL) was heated in an oil bath under N2. 2 NMR yields.…”

Structural Modification Endows Small-Molecular SN38 Derivatives with Multifaceted Functions

“…For instance, many research projects are carried out to structurally modify vinblastine, tropolones, oridonin, etc. [ 1 , 2 , 3 , 4 , 5 ]. Camptothecin derivatives, another important source for the development of antitumor drugs, exert antitumor activity by inhibiting topoisomerase 1.…”

Access to 2-Alkyltropones via Organic Base-Catalyzed Tandem Deamination and Aldol Condensation of Tropinone-Derived Quaternary Ammonium Salts

“…The tropone skeleton exists in a number of natural products and bioactive substances, such as colchicine (a monotherapy for acute gout flares and familial Mediterranean fever), harringtonolide (a potent RACK1 inhibitor), and tropodithietic acid (an antibiotic) (Figure ). While tropones are prototypical nonbenzenoid seven-membered aromatic compounds with a carbonyl group, sporadic examples have shown that they can participate in chemical transformations such as cycloaddition, rearrangement, and substitution . Currently, the applications of substituted tropones are significantly limited by their preparative methods.…”