Diverted Total Synthesis Research Articles

Diverted Total Synthesis of Promysalin Analogs Demonstrates That an Iron-Binding Motif Is Responsible for Its Narrow-Spectrum Antibacterial Activity.

Promysalin is a species-specific Pseudomonad metabolite with unique bioactivity. To better understand the mode of action of this natural product, we synthesized 16 analogs utilizing diverted total synthesis (DTS). Our analog studies revealed that the bioactivity of promysalin is sensitive to changes within its hydrogen bond network whereby alteration has drastic biological consequences. The DTS library not only yielded three analogs that retained potency but also provided insights that resulted in the identification of a previously unknown ability of promysalin to bind iron. These findings coupled with previous observations hint at a complex multifaceted role of the natural product within the rhizosphere.

ChemInform Abstract: Design and Synthesis of Analogues of Natural Products

AbstractReview: [163 refs.

Probing the Anticancer Mechanism of (−)‐Ainsliatrimer A through Diverted Total Synthesis and Bioorthogonal Ligation

AbstractHerein, we report an efficient approach for exploring the novel anticancer mechanism of (−)‐ainsliatrimer A, a structurally complex and unique trimeric sesquiterpenoid, through a combined strategy of diverted total synthesis (DTS) and bioorthogonal ligation (TQ ligation), which allowed us to visualize the subcellular localization of this natural product in live cells. Further biochemical studies facilitated by pretarget imaging revealed that PPARγ, a nucleus receptor, was a functional cellular target of ainsliatrimer A. We also confirmed that the anticancer activity of ainsliatrimer A was caused by the activation of PPARγ.

Probing the anticancer mechanism of (-)-ainsliatrimer A through diverted total synthesis and bioorthogonal ligation.

Herein, we report an efficient approach for exploring the novel anticancer mechanism of (-)-ainsliatrimer A, a structurally complex and unique trimeric sesquiterpenoid, through a combined strategy of diverted total synthesis (DTS) and bioorthogonal ligation (TQ ligation), which allowed us to visualize the subcellular localization of this natural product in live cells. Further biochemical studies facilitated by pretarget imaging revealed that PPARγ, a nucleus receptor, was a functional cellular target of ainsliatrimer A. We also confirmed that the anticancer activity of ainsliatrimer A was caused by the activation of PPARγ.

Directed Orthometalation and the Asymmetric Total Synthesis of N-Deoxymilitarinone A and Torrubiellone B

A diverted total synthesis (DTS) approach to the total synthesis of pyridone alkaloids N-deoxymilitarinone A (8) and torrubiellone B (10) has been developed. The common intermediate 14 was first assembled by a dual directed orthometalation process using a methoxymethyl group as directed metalation group. Other crucial steps include the assembly of polyenes under aldol condensation for DTS using general and concise strategy and diastereoselective synthesis of the syn-dimethyl array by an Evans aldol reaction.

Generation of Molecular Shape Diverstiy. From Privileged Scaffolds to Diverted Total Synthesis

AbstractMolecular shape is a presentation of a molecule’s three-dimensional structure and its volume of space and surface electrostatic potential map collectively define the function, e. g. as a modulator or probe to biological targets. Molecular shape diversity for compound libraries with multiple scaffolds (rich skeletal diversity) is recognized as a prerequisite for discovering broad bioactivity. Established strategies and methodologies for diversity-oriented synthesis (DOS) are useful for generating molecular shape diversity by synthesizing natural product-like compounds. On the other hand, diverted total synthesis (DTS) offers natural products and analogues with a higher degree of structural diversity and complexity. Examples of DOS of privileged heterocycles and DTS of amphidinolide T marine macrolides from the author’s laboratories are illustrated.

Cover Picture: A Diverted Total Synthesis of Mycolactone Analogues: An Insight into Buruli Ulcer Toxins (Chem. Eur. J. 51/2011)

150 Years after the first description of Buruli ulcer, a devastating mycobacterial infection, a diverted total synthesis (DTS) approach of mycolactone analogues has been developed, relying on metal-mediated and metal-catalyzed transformations. These DTS efforts have provided relevant insights into structure–activity relationships based on cytopathic assays on L929 fibroblasts. The lowest concentration inducing a cytopathic effect was determined for selected analogues, allowing a clear picture to emerge by comparison with the natural toxins. For more details, see the Full Paper by N. Blanchard et al. on page 14413 ff. Cover art by David Vandergucht.

The migrastatin family: discovery of potent cell migration inhibitors by chemical synthesis.

The first asymmetric total synthesis of (+)-migrastatin (1), a macrolide natural product with anti-metastatic properties, has been accomplished. Our concise and flexible approach utilized a Lewis acid-catalyzed diene aldehyde condensation (LACDAC) to install the three contiguous stereocenters and the trisubstituted (Z)-alkene of migrastatin (2 + 3 --> 21). Construction of the two remaining stereocenters and incorporation of the glutarimide-containing side chain was achieved by an anti-selective aldol addition of propionyl oxazolidinone 28 to angelic aldehyde 27, followed by a Horner-Wadsworth-Emmons (HWE) coupling of 32 with glutarimide aldehyde 5. Finally, the assembly of the macrocycle was realized by a highly (E)-selective ring-closing metathesis (35 --> 37). Utilizing the power of diverted total synthesis (DTS), a series of otherwise inaccessible analogues was prepared and evaluated for their potential as tumor cell migration inhibitors in several in vitro assays. These studies revealed a dramatic increase in activity when the natural motif was considerably simplified, presenting macrolactones 45 and 48, as well as macrolactam 55, macroketone 60, and CF(3)-alcohol 71 as promising anti-metastatic agents.