Total synthesis of the endogenous inflammation resolving lipid resolvin D2 using a common lynchpin

The total synthesis of the endogenous inflammation resolving eicosanoid resolvin D2 (1) is described. The key steps involved a Wittig reaction between aldehyde 5 and the ylide derived from phosphonium salt 6 to give enyne 17 and condensation of the same ylide with aldehyde 7 to afford enyne 11. Desilylation of 11 followed by hydrozirconation and iodination gave the vinyl iodide 4 and Sonogashira coupling between this compound and enyne 3 provided alkyne 18. Acetonide deprotection, partial reduction and ester hydrolysis then gave resolvin D2 (1).

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Concise Diastereoselective Total Synthesis of (±)-Parvistemonine A

Synlett ◽

10.1055/s-0040-1707283 ◽

2020 ◽

Vol 31 (18) ◽

pp. 1800-1804

Author(s):

Kazuyuki Sugita ◽

Rintaro Matsuo ◽

Ayumu Miyashita ◽

Motoi Kuwabara ◽

Shinya Adachi ◽

...

Keyword(s):

Total Synthesis ◽

Michael Addition ◽

Wittig Reaction ◽

Crystallographic Analysis ◽

Mitsunobu Reaction ◽

X Ray ◽

Linear Sequence ◽

Relative Stereochemistry ◽

Key Steps ◽

First Time

AbstractWe have developed a concise diastereoselective total synthesis of (±)-parvistemonine A. By using a Mukaiyama–Michael addition, an aza-Wittig reaction, a Paal–Knorr pyrrole synthesis, an acid-mediated annulation, and a Mitsunobu reaction as key steps, we achieved a total synthesis in which the longest linear sequence was ten steps and the overall yield was 19.6%. Additionally, the relative stereochemistry of parvistemonine A was confirmed by X-ray crystallographic analysis for the first time.

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Synthesis of myxobacteria metabolites

Pure and Applied Chemistry ◽

10.1351/pac-con-11-11-19 ◽

2012 ◽

Vol 84 (6) ◽

pp. 1421-1433 ◽

Cited By ~ 5

Author(s):

Stephen L. Birkett ◽

Darran A. Loits ◽

Samantha Wimala ◽

Mark A. Rizzacasa

Keyword(s):

Total Synthesis ◽

Biological Activities ◽

Aldol Reaction ◽

Alder Reaction ◽

Diels Alder ◽

Sonogashira Coupling ◽

Partial Reduction ◽

Diels Alder Reaction ◽

Apicularen A ◽

Excellent Source

Myxobacteria are an excellent source of novel secondary metabolites with a range of biological activities. This review details the synthesis of several examples of these natural products. The total synthesis of all the members of the crocacin family is presented where the stereochemistry of the stereotetrad was set via a tin-mediated syn-aldol reaction followed by selective anti-reduction. The other key step in the route to crocacins A, B, and D was the introduction of the enamide functionality by acylation of an enecarbamate. A formal synthesis of apicularen A is also discussed, which involved a base-induced macrolactonization reaction and a transannular oxy-Michael cyclization to secure the tetrahydropyran ring. Finally, the total synthesis of deshydroxyajudazol B is summarized. This route details a modified approach to the 2,4-disubstituted oxazole, and a Diels–Alder reaction followed by aromatization was utilized to form the isochromanone moiety. A highly efficient Sonogashira coupling followed by partial reduction then gave deshydroxyajudazol B.

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Synthesis of Sex Pheromones of the Citrus Leafminer (CLM) (Phyllocnistis citrella)

Natural Product Communications ◽

10.1177/1934578x1801300520 ◽

2018 ◽

Vol 13 (5) ◽

pp. 1934578X1801300

Author(s):

Alleni Suman Kumar ◽

Vavilapalli Satyanarayana ◽

Ahmad Alkhazim Alghamdi ◽

Jhillu Singh Yadav

Keyword(s):

Total Synthesis ◽

Sex Pheromones ◽

Wittig Reaction ◽

Phyllocnistis Citrella ◽

Citrus Leafminer ◽

Key Steps

A convergent and efficient total synthesis of sex Pheromones has been achieved. The synthesis exploits the Wittig reaction, hydrogenation and oxidation as key steps.

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Sonogashira coupling in natural product synthesis

Organic Chemistry Frontiers ◽

10.1039/c3qo00086a ◽

2014 ◽

Vol 1 (5) ◽

pp. 556-566 ◽

Cited By ~ 68

Author(s):

Dan Wang ◽

Shuanhu Gao

Keyword(s):

Natural Products ◽

Total Synthesis ◽

Natural Product ◽

Natural Product Synthesis ◽

Sonogashira Coupling ◽

Key Steps

This review will focus on selected applications of Sonogashira coupling and subsequent transformations as key steps in the total synthesis of natural products.

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Concise Total Synthesis of Curvulone B

Synlett ◽

10.1055/a-1297-6838 ◽

2020 ◽

Author(s):

Debendra K. Mohapatra ◽

Shivalal Banoth ◽

Utkal Mani Choudhury ◽

Kanakaraju Marumudi ◽

Ajit C. Kunwar

Keyword(s):

Total Synthesis ◽

Stereoselective Synthesis ◽

Ring System ◽

Bond Forming ◽

Cross Metathesis ◽

Bond Forming Reactions ◽

Key Steps

AbstractA concise and convergent stereoselective synthesis of curvulone B is described. The synthesis utilized a tandem isomerization followed by C–O and C–C bond-forming reactions following Mukaiyama-type aldol conditions for the construction of the trans-2,6-disubstituted dihydropyran ring system as the key steps. Other important features of this synthesis are a cross-metathesis, epimerization, and Friedel–Crafts acylation.

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Synthesis of 8-HEPE and 10-HDoHE in both (R)- and (S)-Forms via Wittig Reactions with COOH-Ylides

Synlett ◽

10.1055/s-0037-1611976 ◽

2019 ◽

Vol 30 (03) ◽

pp. 338-342

Author(s):

Yuta Suganuma ◽

Shun Saito ◽

Yuichi Kobayashi

Keyword(s):

Docosahexaenoic Acid ◽

Eicosapentaenoic Acid ◽

Wittig Reaction ◽

Phosphonium Salt ◽

Wittig Reactions

Wittig reactions using carboxy (CO2H) ylides derived from a carboxylic phosphonium salt and NaN(TMS)2 (NaHMDS) in a 1:1 ratio were applied to the synthesis of 8-HEPE and 10-HDoHE, which are metabolites of eicosapentaenoic acid and docosahexaenoic acid, respectively. The attempted Wittig reaction of 3-(TBS-oxy)pentadeca-4E,6Z,9Z,12Z-tetraenal with the carboxy ylide (2 equiv) derived from Br– Ph3P+(CH2)4CO2H and NaHMDS (1:1) competed with the elimination of the TBS-oxy group at C3 to give a mixture of the Wittig product and the elimination product in 45–50% and 30–40% yields, respectively. The elimination was suppressed completely by using three equiv of the carboxy ylides in THF/HMPA (7–8:1), and the subsequent desilylation gave 8-HEPE in (R)- and (S)-forms. Similarly, both enantiomers of 10-HDoHE were synthesized.

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First Total Synthesis of a Fluorinated Calystegin

Zeitschrift für Naturforschung B ◽

10.1515/znb-2010-0402 ◽

2010 ◽

Vol 65 (4) ◽

pp. 445-451 ◽

Cited By ~ 5

Author(s):

René Csuk ◽

Erik Prell ◽

Stefan Reißmann ◽

Claudia Korb

Keyword(s):

Total Synthesis ◽

Ring Opening ◽

Competitive Inhibitor ◽

Ring Closure ◽

Target Compound ◽

Metathesis Reaction ◽

Grubbs Catalyst ◽

Ring Opening Reaction ◽

Ultrasound Assisted ◽

Key Steps

A straightforward chiral pool synthesis for the first fluorinated calystegin is described. Key steps of this synthesis include an ultrasound-assisted Zn-mediated tandem ring opening reaction followed by a Grubbs’ catalyst-mediated ring closure metathesis reaction. The target compound is a selective and competitive inhibitor for a β -glycosidase.

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Total Synthesis of S-(+)-Argentilactone

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-0318 ◽

2001 ◽

Vol 56 (3) ◽

pp. 325-328 ◽

Cited By ~ 7

Author(s):

Muhammad Saeed ◽

Muhammad Abbas ◽

Khalid Mohammad Khan ◽

Wolfgang Voelter

Keyword(s):

Total Synthesis ◽

Wittig Reaction ◽

Subsequent Oxidation

Abstract Asymmetrie Total Synthesis Asymmetrie total synthesis of S-(+)-argentilactone (2) was accomplished, using methyl-a-D-glucopyranoside (3) as carbohydrate template. Benzylidene acetal 5 was hydrolysed with tBuOOH/AlCl3 and further manipulated to produce the aldehyde 10. A Wittig reaction and subsequent oxidation of the anomeric position yielded the target argentilactone.

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