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The collaborative total synthesis of darobactin A, a recently isolated antibiotic that selectively targets Gram-negative bacteria, has been accomplished in a convergent fashion with a longest linear sequence of 16 steps from d-Garner's aldehyde and l-serine. Scalable routes toward three non-canonical amino acids were developed to enable the synthesis. The closure of the bismacrocycle was realized through sequential, halogen-selective Larock indole syntheses, where the proper order of cyclizations proved crucial for the formation of the desired atropisomer of the natural product.

A new gold(I)-catalyzed multicomponent synthesis of β-alkoxy ketones from aldehydes, alcohols, and alkynes is described. This atom economical synthesis was achieved through the use of the gold complex (SPhos)AuNTf2 as a catalyst, and allows for the preparation of a diverse array of β-alkoxy ketone products. Mechanistic studies illustrate that these reactions proceed via gold(I)-catalyzed hydrolysis of the alkyne to an aryl ketone, which then undergoes an aldol reaction with an oxocarbenium ion generated in situ from the aldehyde and alcohol components. [ABSTRACT FROM AUTHOR]