Stereoselective Total Synthesis of (6S)-5,6-Dihydro-6-[(2R)-2-hydroxy-6-phenylhexyl]-2H-pyran-2-one from L-Malic Acid

A stereoselective total synthesis of an antiproliferative and antifungal natural product, (6 S)-5,6-dihydro-6-[(2 R)-2-hydroxy-6-phenylhexyl]-2 H-pyran-2-one has been accomplished using the Barbier allylation, LiAlH4/LiI mediated syn-stereoselective reduction and olefin ring-closing metathesis (RCM) as the key steps. L-Malic acid was used as a chiral precursor for the construction of syn-1,3-diol moiety of the molecule.

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Stereoselective Total Syntheses of (3R,5R)-Sonnerlactone and (3R,5S)-Sonnerlactone

Natural Product Communications ◽

10.1177/1934578x1701200925 ◽

2017 ◽

Vol 12 (9) ◽

pp. 1934578X1701200

Author(s):

Supriya Ghanty ◽

P. Rasvan Khan ◽

B. V. Subba Reddy

Keyword(s):

Malic Acid ◽

Ring Closing Metathesis ◽

Total Syntheses ◽

Key Steps ◽

Barbier Allylation

A highly convergent and concise total syntheses of (3 R,5 R)-Sonnerlactone and (3 R,5 S) Sonnerlactone from a readily available L-malic acid is described. The following series of reactions such as Barbier allylation, photochemical esterification and Ring Closing Metathesis (RCM) are utilized as key steps to accomplish their syntheses.

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A Chemoenzymatic Total Synthesis of the Undecenolide ( - )-Cladospolide C

Australian Journal of Chemistry ◽

10.1071/ch05074 ◽

2005 ◽

Vol 58 (7) ◽

pp. 511 ◽

Cited By ~ 14

Author(s):

Martin G. Banwell ◽

David T. J. Loong ◽

Anthony C. Willis

Keyword(s):

Total Synthesis ◽

Single Crystal ◽

Natural Product ◽

Absolute Configuration ◽

Starting Material ◽

Unsaturated Ester ◽

Ring Closing Metathesis ◽

X Ray ◽

Key Steps ◽

First Time

The (−)-enantiomer, ent-3, of the natural product (+)-cladospolide C (3) has been prepared for the first time using the monochiral cis-1,2-dihydrocatechol 5 as starting material. Key steps include coupling of the derived acid 6 with the enzymatically generated (S)-(+)-4-penten-2-ol (7) and ring-closing metathesis (RCM) of the resultant doubly unsaturated ester 8 to give lactone 9. The structure of this last compound has been confirmed by single-crystal X-ray analysis. This work has established that the absolute configuration of (+)-cladospolide C has been correctly assigned and is as illustrated in structure 3.

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The Structure Elucidation of Haprolid

Synthesis ◽

10.1055/s-0036-1591836 ◽

2017 ◽

Vol 50 (03) ◽

pp. 529-538 ◽

Cited By ~ 1

Author(s):

Markus Kalesse ◽

Jun Li ◽

Jun Xing ◽

Daniel Lücke ◽

Dennis Lübken ◽

...

Keyword(s):

Total Synthesis ◽

Natural Product ◽

Structure Elucidation ◽

Carcinoma Cell ◽

Hidden Markov ◽

Biological Evaluation ◽

Terminal Olefin ◽

Carcinoma Cell Lines ◽

Hepatocellular Carcinoma Cell ◽

Key Steps

The assignment of two stereocenters of the natural product haprolid through the application of a profile hidden Markov model (HMM) and its confirmation through total synthesis of the natural product and of two of its diastereomers are reported. The structure elucidation of this polyketide-peptide hybrid natural product is a telling showcase of how difficult it can be to determine the absolute configuration of isolated stereocenters and the benefits of a gene cluster analysis for structure determination. The key steps of the synthesis are a selective epoxidation of a terminal olefin and the stereodivergent macrolactonization strategy. Furthermore, the biological evaluation of all products showed that all diastereomers are potent inhibitors of hepatocellular carcinoma cell lines.

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Enantioselective total synthesis of (S)-nakinadine B

RSC Advances ◽

10.1039/c6ra03915d ◽

2016 ◽

Vol 6 (31) ◽

pp. 25913-25917 ◽

Cited By ~ 10

Author(s):

Yuvraj Garg ◽

Satyendra Kumar Pandey

Keyword(s):

Total Synthesis ◽

Natural Product ◽

Michael Addition ◽

Marine Natural Product ◽

Enantioselective Total Synthesis ◽

Novel Approach ◽

Key Steps

A novel approach for the synthesis of (S)-nakinadine B, a marine natural product is described. The synthesis utilizes the optimized combination of organocatalyzed Michael addition and aminoxylation reactions as key steps.

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A Concise and Stereoselective Total Synthesis of Paecilomycin E

Natural Product Communications ◽

10.1177/1934578x1901400135 ◽

2019 ◽

Vol 14 (1) ◽

pp. 1934578X1901400

Author(s):

A. Srinivas Reddy ◽

Gundamalla Bhavani ◽

Sandhya Jonnala ◽

Rajashaker Bantu ◽

B. V. Subba Reddy

Keyword(s):

Total Synthesis ◽

Ring Closing Metathesis ◽

Key Steps ◽

Acid Unit

A concise approach for the first total synthesis of paecilomycin E is described involving Alder-Rickert reaction, Mitsunobu esterification and ring closing metathesis as the key steps. This approach has successfully demonstrated the Alder-Rickert protocol for the construction of resorcylic acid unit.

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Synthesis of Carbocyclic Nucleosides (+)-Neplanocin A, (+)-Aristeromycin and 4'-epi-(+)-Aristeromycin from D-Fructose

Letters in Organic Chemistry ◽

10.2174/1570178615666181023145502 ◽

2019 ◽

Vol 16 (9) ◽

pp. 750-758

Author(s):

Perali R. Sridhar ◽

Vennam D.K. Reddy ◽

Mandava Suresh ◽

Nadiveedhi M. Reddy ◽

K. Shiva Kumar

Keyword(s):

Total Synthesis ◽

Allylic Alcohol ◽

Starting Material ◽

Carbocyclic Nucleosides ◽

Ring Closing Metathesis ◽

Neplanocin A ◽

Oxidative Rearrangement ◽

Key Steps

D-Fructose is used as the chiral pool starting material for the stereoselective total synthesis of (+)-neplanocin A. Zinc mediated fragmentation, ring-closing metathesis and oxidative rearrangement of cyclic tertiary allylic alcohol are used as the key steps in achieving the synthesis of key carbocylic intermediate. Further, stereoselective total synthesis of 4'-epi-(+)-aristeromycin and the conversion of (+)-neplanocin A to a mixture of (+)-aristeromycin and 4'-epi-(+)-aristeromycin are described.

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Total Synthesis of (–)-Aristoquinoline via an Intramolecular Nitrilium Ion Cyclization

Synthesis ◽

10.1055/s-0041-1737276 ◽

2021 ◽

Author(s):

Keith P. Reber ◽

Priyansh D. Gujarati

Keyword(s):

Total Synthesis ◽

Natural Product ◽

Building Block ◽

Spectroscopic Properties ◽

Ring System ◽

Synthetic Route ◽

Enantioselective Total Synthesis ◽

Key Steps

AbstractThe enantioselective total synthesis of the alkaloid aristoquinoline has been achieved in seven steps and 26% overall yield. A new preparation of the useful synthetic building block (–)-α-terpinyl amine was also developed in order to avoid stoichiometric mercury reagents or azide-containing intermediates. Key steps in the optimized synthetic route include an intramolecular nitrilium ion cyclization to form the characteristic azabicyclo[3.3.1]nonane ring system and a diastereoselective reduction of the resulting imine mixture to afford the natural product. An isomer of aristoquinoline containing an exocyclic alkene was also obtained and found to exhibit unusual chromatographic and spectroscopic properties.

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Chiron approach for the total synthesis of brevipolide M

Synlett ◽

10.1055/a-1730-9857 ◽

2022 ◽

Author(s):

Yang Liu ◽

Ziyang Zhao ◽

Chao Hu ◽

Chuanfang Zhao ◽

Jun Liu ◽

...

Keyword(s):

Double Bond ◽

Total Synthesis ◽

Stereoselective Synthesis ◽

Ring Closing Metathesis ◽

One Pot ◽

Double Bond Migration ◽

Key Steps

An efficient stereoselective synthesis of brevipolide M was established in 13 linear steps and 17.8% overall yields base on chiron approach. The key steps of our synthesis involved tandem homologation / tetrahydrofuran cyclization and sequential ring-closing metathesis (RCM) / double-bond migration in one-pot processes.

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Protecting-Group-Free Total Synthesis of Anticancer (±)-Melotenine A

Synthesis ◽

10.1055/a-1633-8333 ◽

2021 ◽

Author(s):

Adisak Thanetchaiyakup ◽

Hassayaporn Rattanarat ◽

Sudaporn Aree ◽

Tanwawan Duangthongyou ◽

Tanin Nanok ◽

...

Keyword(s):

Total Synthesis ◽

Human Cancer ◽

Alder Reaction ◽

Diels Alder ◽

Protecting Groups ◽

Protecting Group ◽

Ring Closing Metathesis ◽

Human Cancer Cell Lines ◽

Diels Alder Reaction ◽

Key Steps

Melotenine A, isolated from Melodinus tenuicaudatus, possesses significant anticancer activity against several human cancer cell lines. The synthesis of (±)-melotenine A was achieved without the use of any protecting groups in 11 steps with an overall yield of 7%. The key steps of our strategy were the Diels–Alder reaction to construct the tetracyclic framework and ring-closing metathesis to form the seven-membered ring of (±)-melotenine A.

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