67122-27-4

Usage

InChI:InChI=1/C6H7NO4/c1-3-4(6(9)10-2)5(8)7-11-3/h1-2H3,(H,7,8)

Upstream product

• 113934-48-8 2-(1-Hydroxy-ethylidene)-malonic acid dimethyl ester 
• 22398-15-8 dimethyl 2-(1-methoxyethylidene)malonate 

Downstream Products

• 115886-03-8 3-(benzyloxy)-5-methyl-4-isoxazolecarboxylic acid 
• 67122-30-9 3-benzyloxy-5-methoxycarbonylmethyl-isoxazole-4-carboxylic acid methyl ester 

Relevant academic research and scientific papers

Total synthesis of viridicatumtoxin B and analogues thereof: Strategy evolution, structural revision, and biological evaluation

The details of the total synthesis of viridicatumtoxin B (1) are described. Initial synthetic strategies toward this intriguing tetracycline antibiotic resulted in the development of key alkylation and Lewis acid-mediated spirocyclization reactions to form the hindered EF spirojunction, as well as Michael-Dieckmann reactions to set the A and C rings. The use of an aromatic A-ring substrate, however, was found to be unsuitable for the introduction of the requisite hydroxyl groups at carbons 4a and 12a. Applying these previous tactics, we developed stepwise approaches to oxidize carbons 12a and 4a based on enol- and enolate-based oxidations, respectively, the latter of which was accomplished after systematic investigations that revealed critical reactivity patterns. The herein described synthetic strategy resulted in the total synthesis of viridicatumtoxin B (1), which, in turn, formed the basis for the revision of its originally assigned structure. The developed chemistry facilitated the synthesis of a series of viridicatumtoxin analogues, which were evaluated against Gram-positive and Gram-negative bacterial strains, including drug-resistant pathogens, revealing the first structure-activity relationships within this structural type.

Total synthesis and structural revision of viridicatumtoxin B

Will the real viridicatumtoxin B please stand up: The total synthesis of viridicatumtoxin B resulted in its structural revision and opens the way for analogue construction and biological evaluation of this complex tetracycline-like antibiotic. The highly convergent strategy employed allows for swift construction of the entire carbocyclic framework of the molecule. Copyright