title: Two versatile and parallel approaches to highly symmetrical open and closed natural product-based structures.
abstract: Two parallel approaches for preparing diverse and highly symmetrical homohybrids derived from a series of mono- and diterpenes, steroids, and alkaloids are reported. Both procedures are based on the mono-addition of bis(alkynyl) dilithium reagents to natural products having a carbonyl group to produce the corresponding alkynyl derivatives. The Glaser-Hay Cu-promoted homocoupling of these alkynyl natural product mono-adducts as well as the Huisgen Cu-catalyzed azide-alkyne cycloaddition (CuAAC) reaction resulted in the synthesis of steroid-, terpene-, and alkaloid-based homohybrid derivatives incorporating diverse spacers to join the natural product scaffolds. Straightforward entries to novel closed highly symmetrical and complex estrone-based macrocyclic and cage architectures by means of the Glaser-Eglinton homocoupling and the CuAAC reaction have been devised.
authors.affiliation: Instituto de Química Orgánica General, Consejo Superior de Investigaciones Científicas, Juan de la Cierva 3, 28006 Madrid, Spain.
authors.forename: Héctor E
authors.initials: HE
authors.lastname: Montenegro
authors.forename: Pedro
authors.initials: P
authors.lastname: Ramírez-López
authors.forename: María C
authors.initials: MC
authors.lastname: de la Torre
authors.forename: María
authors.initials: M
authors.lastname: Asenjo
authors.forename: Miguel A
authors.initials: MA
authors.lastname: Sierra
mesh_terms: D000470:Alkaloids / Q000737:chemistry; D000480:Alkynes / Q000737:chemistry; D001688:Biological Products / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry; D003500:Cyclization; D008094:Lithium / Q000737:chemistry; D047028:Macrocyclic Compounds / Q000737:chemistry; D013256:Steroids / Q000737:chemistry; D013729:Terpenes / Q000737:chemistry
chemical_list: D000470:Alkaloids; D000480:Alkynes; D001688:Biological Products; D047028:Macrocyclic Compounds; D013256:Steroids; D013729:Terpenes; D003300:Copper; D008094:Lithium