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Three renieramycin-type antitumor alkaloids, (-)-jorunnamycins A (1) and C (2) and (-)-jorumycin (3), have been synthesized by a new convergent approach, which features a highly regio- and stereoselective Pictet-Spengler cyclization to couple the isoquinoline and the trisubstituted phenylalaninol partners. This synthetic strategy opens an economical access to these important antitumor alkaloids with high yields: (-)-jorunnamycin A, as a common precursor to other renieramycin-type alkaloids and their analogues, is obtained with 18.1% overall yield from l-tyrosine.

The present work shows a new contribution to the design of superhydrophobic surfaces with the additional function of active corrosion protection, through the encapsulation of inhibiting agents.

A series of chiral 5,6-dihydro-1,4-oxazin-2-one substrates, as preformed cyclic aldimines and ketoimines, were employed to develop a new asymmetric Ugi three-component reaction for the first time. The Ugi reaction of the imines, isocyanides, and carboxylic acids opens an efficient access to novel morpholin-2-one-3-carboxamide compounds. The chiral imines showed promising stereoinduction for the new chiral center of the Ugi products, and predominant trans-isomers were obtained in the most cases. Addition of some Lewis acids or proton acids could improve the diastereoselectivity further but usually led to a drop in total yield. The Ugi-3CR could be extended to the stereoselective synthesis of ketopiperazine-2-carboxamide derivatives.

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