Synthetic investigations towards the structurally complex and highly decorated framework of B-seco limonoid natural products by means of a [3,3]-sigmatropic rearrangement are described. Detailed model studies reveal, that an Ireland-Claisen rearrangement can be employed to construct the central C9-C10 bond thereby giving access to the B-seco limonoid scaffold. However, application of the develo...

Glycoglycerolipids occur widely in natural products, especially in the marine species. Glycoglycerolipids have been shown to possess a variety of bioactivities. This paper will review the different methodologies and strategies for the synthesis of biological glycoglycerolipids and their analogs for bioactivity assay. In addition, the bioactivities and structure-activity relationship of the glyc...

Discovering new carbon building blocks is very significant to advance transition-metal-catalyzed cycloadditions for the synthesis of various-sized ring compounds. A new seven-carbon building block from buta-1,3-dienylcyclopropanes (BDCPs) has been developed, showing that, under the catalysis of [Rh(CO)(2)Cl](2), BDCPs react with CO to give [7 + 1] cycloaddition products, cyclooctadienones. The ...

Because of the highly unique structures of marine natural products, there are many examples of structures that were originally proposed based on spectral analyses but later proven incorrect. In many cases, the total syntheses of the originally proposed structures of marine natural products has confirmed their incorrectness and the subsequent total syntheses of the newly proposed structures prov...

A simple evolutionary model is presented which explains why organisms produce so many natural products, why so many have low biological activity, why enzymes involved in natural product synthesis have the properties they do and why natural product metabolism is shaped as it is.

After an initial period of validating asymmetric organocatalysis by using a wide range of important model reactions that constitute the essential tools of organic synthesis, the time has now been reached when organocatalysis can be used to address specific issues and solve pending problems of stereochemical relevance. This Review deals with selected studies reported in 2006 and the first half o...

Fusarins G1/G2 (1/2) and G3/G4 (3/4), two sets of interesting examples of diastereoisomers with substantially identical NMR data, were discovered from natural products. The reason was discussed and the generally applicable determinant conditions were proposed. The minimum interval for stereoclusters to be entirely segregated was also discussed.

A spiro[5.5]ketal library embodying the core structure of numerous biologically active natural products was synthesized employing a double intramolecular hetero Michael reaction as a key transformation.