Studies culminating in the total synthesis and determination of the absolute configuration of (−)-saudin

Boeckman, Robert K.; Ferreira, Maria Rico del Rosario; Mitchell, Lorna H.; Shao, Pengcheng; Neeb, Michael J.; Fang, Yong

doi:10.1016/j.tet.2011.09.067

Cited by 8 publications

(12 citation statements)

References 54 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…95 Examples for titanium(IV)-promoted aliphatic Claisen rearrangements have also been reported. [96][97][98] We refrain from being comprehensive in this matter and, therefore, take the liberty to present only a personal selection of landmark contributions. Quite generally, in order to exploit aluminum(III) compounds as rate accelerators for aliphatic Claisen rearrangements, at least stoichiometric amounts of the Lewis acid are required.…”

Section: Lewis Acid Mediated Claisen Rearrangements: the Aluminum Agementioning

confidence: 99%

Claisen Rearrangement of Aliphatic Allyl Vinyl Ethers from 1912 to 2012: 100 Years of Electrophilic Catalysis

Rehbein

Hiersemann

2013

Synthesis

View full text Add to dashboard Cite

This review summarizes, from a personal perspective, the development of catalytic asymmetric Claisen rearrangements from 1912 to 2012. 1 Introduction 2 Gosteli-Claisen Rearrangement 3 Claisen Rearrangement Using Stable Enols: Kojic Acid and Diosphenols 4 The Early Years: Catalysis by Brønsted Acids 5 Lewis Acid Mediated Claisen Rearrangements: The Aluminum Age 6 Catalysis by Precious Metals 7 Catalysis by σ-Lewis Acids 8 Catalysis by Achiral Organocatalysts 9 Catalytic Asymmetric Claisen Rearrangements 10 Conclusion

show abstract

Section: Lewis Acid Mediated Claisen Rearrangements: the Aluminum Agementioning

confidence: 99%

Claisen Rearrangement of Aliphatic Allyl Vinyl Ethers from 1912 to 2012: 100 Years of Electrophilic Catalysis

Rehbein

Hiersemann

2013

Synthesis

View full text Add to dashboard Cite

show abstract

“…The absolute configuration could not be determined, but was assigned by its close analogy with saudin, for which the configuration has been established by unequivocal synthesis. 23 Lanceolide O (15) (Figure 4) was isolated as a colorless gum with the elemental formula C 20 H 22 O 9 determined by the HRESIMS (Figure S186, Supporting Information). This compound is thus an isomer of 14.…”

Section: ■ Results and Discussionmentioning

confidence: 99%

Compounds Related to Saudin and Three New Series of Diterpenoids from Clutia lanceolata

et al. 2023

View full text Add to dashboard Cite

Clutia lanceolata is a medicinal plant native to Ethiopia and sub-Saharan Africa and to the Arabian Peninsula. It is used traditionally in Saudi Arabia for the treatment of diabetes. Previous phytochemical analysis of this species has been limited to the identification of methylthiocoumarins. Further work has led to isolation of 19 new diterpenoids in three structural classes. Their structures were established by HRMS and by a range of NMR techniques (1H, 13C, COSY, NOESY, HSQC, HMBC), with confirmation for some examples by X-ray crystallography. NOESY and 1H–1H NMR coupling constants gave the relative stereochemical configurations and conformational information, with absolute configurations being established through X-ray crystallography. One example closely related to the known hypoglycemic compound saudin (found in C. richardiana and also in C. lanceolata) and one with a different core tetracycle were found to enhance strongly the glucose-triggered release of insulin from murine pancreatic islets. Biosynthetic proposals for the three groups of new diterpenoids by alternative cyclization of a common precursor are put forward. Lanceolide P (16) is proposed as a lead compound for further development for the treatment of diabetes.

show abstract

“…The keto group in 13 was protected as its ketal using ethylene glycol 17 in the presence of catalytic amounts of p-toluenesulfonic acid to afford 14. Deprotection of the silyl ether in 14 using TBAF furnished the alcohol 15, which on oxidation using DMP 18 yielded the aldehyde 16.…”

Section: Resultsmentioning

confidence: 99%

Stereoselective total synthesis of (−)-nupharamine utilizing an α-chlorosulfide and a sulfinimine for C–C bond formation

Raghavan

Sheelamanthula

2016

Org. Biomol. Chem.

View full text Add to dashboard Cite

An efficient stereoselective synthesis of the nuphar alkaloid, (-)-nupharamine, is reported. The key features include the Lewis acid catalyzed reaction of an α-chlorosulfide with a silyl ketene acetal for C-C bond formation, creation of the stereocenter at C2 by a diastereoselective reaction of allyl indium with a sulfinimine and reductive amination for the introduction of the C6 stereocenter of the piperidine ring.

show abstract

Studies culminating in the total synthesis and determination of the absolute configuration of (−)-saudin

Cited by 8 publications

References 54 publications

Claisen Rearrangement of Aliphatic Allyl Vinyl Ethers from 1912 to 2012: 100 Years of Electrophilic Catalysis

Claisen Rearrangement of Aliphatic Allyl Vinyl Ethers from 1912 to 2012: 100 Years of Electrophilic Catalysis

Compounds Related to Saudin and Three New Series of Diterpenoids from Clutia lanceolata

Stereoselective total synthesis of (−)-nupharamine utilizing an α-chlorosulfide and a sulfinimine for C–C bond formation

Contact Info

Product

Resources

About