scholarly journals Total synthesis of the actinoallolides and a designed photoaffinity probe for target identification

2020 ◽  
Vol 18 (40) ◽  
pp. 8109-8118
Author(s):  
Matthew J. Anketell ◽  
Theodore M. Sharrock ◽  
Ian Paterson
Keyword(s):  
Natural Products ◽  
Total Synthesis ◽  
Late Stage ◽  
Target Identification ◽  
Convergent Synthesis

A convergent synthesis of the actinoallolides with late-stage diversification provides access to a photoaffinity probe to identify the target of these potent anti-trypanosomal natural products.

scholarly journals Nickel-Catalyzed Three-Component Olefin Reductive Dicarbofunctionalization to Access Highly Functionalized Alkylborates

2020 ◽  
Author(s):  
Xiao-Xu Wang ◽  
Xi Lu ◽  
Shi-Jiang He ◽  
Yao Fu
Keyword(s):  
Natural Products ◽  
Late Stage ◽  
Functional Group ◽  
Coupling Efficiency ◽  
Convergent Synthesis ◽  
Drug Molecules ◽  
Aryl Iodides ◽  
Alkyl Bromides ◽  
Vinyl Boronates ◽  
Convenient Access

We report a three-component olefin reductive dicarbofunctionalization for constructing densely functionalized alkylborates, specifically, nickel-catalyzed reductive dialkylation and alkylarylation of vinyl boronates with a variety of alkyl bromides and aryl iodides. This reaction exhibits good coupling efficiency and excellent functional group compatibility, providing convenient access to the late-stage modification of complex natural products and drug molecules. Combined with versatile alkylborate transformations, this reaction could also find applications in the modular and convergent synthesis of complex, densely functionalized compounds.

Synthetic approaches to [5,6]-benzannulated spiroketal natural products

2011 ◽  
Vol 84 (6) ◽  
pp. 1379-1390 ◽  
Author(s):  
Michael C. McLeod ◽  
Margaret A. Brimble ◽  
Dominea C. K. Rathwell ◽  
Zoe E. Wilson ◽  
Tsz-Ying Yuen
Keyword(s):  
Natural Products ◽  
Total Synthesis ◽  
Electronic Properties ◽  
Late Stage ◽  
Biologically Active ◽  
Formal Synthesis ◽  
Berkelic Acid ◽  
Synthetic Approaches

Studies toward the synthesis of three biologically active [5,6]-benzannulated spiroketal natural products are described. The first total synthesis of paecilospirone is reported, employing a late-stage, pH-neutral spiroketalization. A formal synthesis of γ-rubromycin is described, where the spiroketal moiety is formed by delicate manipulation of the electronic properties of the spirocyclization precursor. Finally, model work toward the total synthesis of berkelic acid is summarized, introducing a novel Horner–Wadsworth–Emmons/oxa-Michael (HWE/oxa-M) cascade to access the spiroketal precursor.

scholarly journals Total Synthesis of Phorbazole B

Molecules ◽  
2020 ◽  
Vol 25 (20) ◽  
pp. 4848
Author(s):  
Yngve Guttormsen ◽  
Magnus E. Fairhurst ◽  
Sunil K. Pandey ◽  
Johan Isaksson ◽  
Bengt Erik Haug ◽  
...  
Keyword(s):  
Natural Products ◽  
High Resolution ◽  
Secondary Metabolites ◽  
Total Synthesis ◽  
Cancer Cells ◽  
Marine Sponge ◽  
Inhibitory Activity ◽  
Late Stage ◽  
Nmr Techniques

Phorbazoles are polychlorinated heterocyclic secondary metabolites isolated from a marine sponge and several of these natural products have shown inhibitory activity against cancer cells. In this work, a synthesis of the trichlorinated phorbazole B using late stage electrophilic chlorination was developed. The synthesis relied on the use of an oxazole precursor, which was protected with an iodine in the reactive 4-position, followed by complete chlorination of all pyrrole positions. Attempts to prepare phorbazole A and C, which contain a 3,4-dichlorinated pyrrole, were unsuccessful as the desired chlorination pattern on the pyrrole could not be obtained. The identities of the dichlorinated intermediates and products were determined using NMR techniques including NOESY/ROESY, 1,1-ADEQUATE and high-resolution CLIP-HSQMBC.

scholarly journals Nickel-Catalyzed Three-Component Olefin Reductive Dicarbofunctionalization to Access Highly Functionalized Alkylborates

2020 ◽  
Author(s):  
Xiao-Xu Wang ◽  
Xi Lu ◽  
Shi-Jiang He ◽  
Yao Fu
Keyword(s):  
Natural Products ◽  
Late Stage ◽  
Functional Group ◽  
Coupling Efficiency ◽  
Convergent Synthesis ◽  
Drug Molecules ◽  
Aryl Iodides ◽  
Alkyl Bromides ◽  
Vinyl Boronates ◽  
Convenient Access

We report a three-component olefin reductive dicarbofunctionalization for constructing densely functionalized alkylborates, specifically, nickel-catalyzed reductive dialkylation and alkylarylation of vinyl boronates with a variety of alkyl bromides and aryl iodides. This reaction exhibits good coupling efficiency and excellent functional group compatibility, providing convenient access to the late-stage modification of complex natural products and drug molecules. Combined with versatile alkylborate transformations, this reaction could also find applications in the modular and convergent synthesis of complex, densely functionalized compounds.

Tungsten-Promoted Hetero-Pauson–Khand Cycloaddition: Application to the Total Synthesis of (–)-Allosecurinine

Synthesis ◽  
2019 ◽  
Vol 51 (09) ◽  
pp. 2001-2006 ◽  
Author(s):  
Egor Chirkin ◽  
Chouaha Bouzidi ◽  
François-Hugues Porée
Keyword(s):  
Natural Products ◽  
Total Synthesis ◽  
Intramolecular Cyclization ◽  
Late Stage ◽  
Ring System ◽  
Enantioselective Synthesis

Herein, we report a concise enantioselective synthesis of (–)-allosecurinine, a tetracyclic Securinega alkaloid featuring an α,β-unsaturated γ-lactone moiety. Starting from inexpensive and readily available trans-l-hydroxyproline, our strategy entails a rare late-stage [2+2+1]-hetero-Pauson–Khand cycloaddition between a ketone and an alkyne as the key complexity-generating step to rapidly install the CD-ring system. The reported W(CO)6-promoted intramolecular cyclization provides the first example of a tungsten-mediated hetero-Pauson–Khand reaction. This approach to the strained bicyclic CD motif present in ­allosecurinine provides some insights into the boundaries of this potentially powerful methodology that might be further extended to other butenolide-containing natural products.

scholarly journals Synthesis of ramariolide natural products and discovery of their targets in mycobacteria

2017 ◽  
Vol 53 (1) ◽  
pp. 107-110 ◽  
Author(s):  
Johannes Lehmann ◽  
Johannes Richers ◽  
Alexander Pöthig ◽  
Stephan A. Sieber
Keyword(s):  
Natural Products ◽  
Total Synthesis ◽  
Target Identification

The total synthesis of ramariolides A–D and ABPP (photoprobe) derivatives have been synthesized for target identification in mycobacterial strains.

scholarly journals Total synthesis of biseokeaniamides A–C and late-stage electrochemically-enabled peptide analogue synthesis

2020 ◽  
Vol 11 (39) ◽  
pp. 10752-10758 ◽  
Author(s):  
Yutong Lin ◽  
Lara R. Malins
Keyword(s):  
Natural Products ◽  
Total Synthesis ◽  
Late Stage ◽  
Peptide Analogue ◽  
Rapid Access ◽  
Structural Analogues

A late-stage electrochemical decarboxylation enables rapid access to structural analogues of biseokeaniamides A–C, cytotoxic lipopeptide natural products.

Studies towards the total synthesis of ouabagenin

2005 ◽  
Vol 83 (6-7) ◽  
pp. 728-740 ◽  
Author(s):  
Ling Chen ◽  
Pierre Deslongchamps
Keyword(s):  
Organic Chemistry ◽  
Natural Products ◽  
Total Synthesis ◽  
Michael Reaction ◽  
Alder Reaction ◽  
Diels Alder ◽  
Convergent Synthesis ◽  
Diels Alder Reaction

An anionic cyclization strategy developed in our laboratory was used to produce a versatile and convergent synthesis of an advanced tetracyclic intermediate for the construction of ouabagenin and closely related analogs.Key words: organic chemistry, synthesis, cycloaddition, polycyclization, Michael reaction, Diels–Alder reaction, steroids, oubain, ouabagenin, natural products.

Sign in / Sign up

Export Citation Format

Share Document