Studies towards the total synthesis of (−)-borrelidin: a strategy for the construction of the C11–C15 cyanodiene fragment and the utility of RCM for macrocyclization using model systems

Krishna, C. Vamsee; Maitra, Soumyajit; Dev, R. Vasu; Mukkanti, K.; Iqbal, Javed

doi:10.1016/j.tetlet.2006.06.092

Cited by 11 publications

(4 citation statements)

References 44 publications

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confidence: 66%

“…The resulting PSAN hydrochloride salts were water-soluble and stable to autoreaction (D 2 O, 24 h). Stereochemical configurations were tentatively assigned by analogy to literature precedent 24 and confirmed by single-crystal X-ray analysis of Z-14a (Figure S2). 26 Next, we tested the reactivity of these trisubstituted olefin PSAN warheads E-14a and Z-14a in comparison to the disubstituted olefin BAY 11-7082 (8) (Figure 2b).…”

supporting

confidence: 66%

“…Thus, PSAN isomers E -14a and Z -14a were prepared from triphenylphosphonium ylide 11 by bromination, olefination, 24 sulfonylation 25 ( E / Z isomers separable), and deprotection with in situ generated anhydrous HCl ( Figure 2 a). The resulting PSAN hydrochloride salts were water-soluble and stable to autoreaction (D 2 O, 24 h).…”

mentioning

confidence: 99%

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Design and Semisynthesis of Biselectrophile-Functionalized Ubiquitin Probes To Investigate Transthioesterification Reactions

Delos Reyes,

Lux,

Hann

et al. 2024

Org. Lett.

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Ubiquitin (Ub) regulates a wide array of cellular processes through post-translational modification of protein substrates. Ub is conjugated at its C-terminus to target proteins via an enzymatic cascade in which covalently bound Ub thioesters are transferred from E1 activating enzymes to E2 conjugating enzymes, and then to certain E3 protein ligases. These transthioesterification reactions proceed via transient tetrahedral intermediates. A variety of chemical strategies have been used to capture E1–Ub–E2 and E2–Ub–E3 mimics, but these introduce modifications that disrupt atomic spacing at the linkage point relative to the native tetrahedral intermediate. We have developed a biselectrophilic PSAN warhead that can be installed in place of the conserved C-terminal glycine in Ub and used to form ternary protein complexes linked via cyanomethyldithioacetals that closely mimic the native tetrahedral intermediates. Investigation of the reactivity of the warhead and substituted analogues led to an effective semisynthetic route to Ub–1-PSAN, which was used to form a ternary E1–Ub*–E2 complex as a mimic of the transthioesterification intermediate.

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confidence: 66%

supporting

confidence: 66%

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Design and Semisynthesis of Biselectrophile-Functionalized Ubiquitin Probes To Investigate Transthioesterification Reactions

Delos Reyes,

Lux,

Hann

et al. 2024

Org. Lett.

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“…This interesting biological profile as well as the structural complexity of borrelidin has prompted substantial synthetic effort toward its total synthesis. Recently, four total syntheses of borrelidin have been reported by the representative groups of Morken, Hanessian, Theodorakis, and ours, and three studies toward the total synthesis have been presented. − Herein, we provide a complete account of our synthetic studies.…”

Section: Introductionmentioning

confidence: 99%

Total Synthesis of Borrelidin

et al. 2007

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The total synthesis of borrelidin has been achieved. The best feature of our synthetic route is macrocyclization at C11-C12 for the construction of an 18-membered ring after esterification between two segments. A detailed examination of the macrocyclization led us to the samarium(II) iodide-mediated intramolecular Reformatsky-type reaction as the most efficient synthetic approach. The two key segments were synthesized through regioselective methylation, directed hydrogenation, stereoselective Reformatsky-type reaction, and MgBr2.Et2O-mediated chelation-controlled allylation.

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Olefin Ring‐Closing Metathesis

Yet

2016

Organic Reactions

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The olefin ring‐closing metathesis reaction catalyzed by ruthenium and molybdenum complexes has been employed in the syntheses of carbocycles, heterocycles, supramolecular compounds, and in tandem metathesis reactions. Chiral ruthenium and molybdenum catalysts have provided high enantiomeric and diastereomeric excesses in ring‐closing metathesis reactions. Many of the unsuccessful medium‐ and large‐sized ring formations which were unsuccessful by traditional methods, such as the intramolecular Wittig, Horner–Wadsworth–Emmons, and Julia–Kocienski reactions, can now be formed by olefin ring‐closing metathesis reactions. Ring‐closing metathesis has been a key step and sometimes the only successful method for the synthesis of numerous natural products and drug discovery targets. The objective of this chapter is to provide an updated, comprehensive coverage of the literature of the olefin ring‐closing metathesis reaction and related processes. Key mechanistic points are summarized.

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Studies towards the total synthesis of (−)-borrelidin: a strategy for the construction of the C11–C15 cyanodiene fragment and the utility of RCM for macrocyclization using model systems

Cited by 11 publications

References 44 publications

Design and Semisynthesis of Biselectrophile-Functionalized Ubiquitin Probes To Investigate Transthioesterification Reactions

Design and Semisynthesis of Biselectrophile-Functionalized Ubiquitin Probes To Investigate Transthioesterification Reactions

Total Synthesis of Borrelidin

Olefin Ring‐Closing Metathesis

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