A synthesis of (+)-D-forosamine was developed. The sugar-scaffold was constructed by a new domino-Knoevenagel-hetero-Diels-Alder reaction from easily available starting materials.
For the synthesis of novel spinosyn analogues, the selective introduction of the 2‐deoxyamino sugar, D‐forosamine, necessary for their bioactivity, is described. The reactions of different alcohol acceptors with the D‐forosamine donor in the presence of iodine and Et3SiH gave the corresponding glycosides in yields of up to 96 % and with an α/β selectivity of 2:3.
The three‐component domino Knoevenagel/hetero‐Diels–Alder reaction of nitroacetone (6), formaldehyde and ethoxyvinylacetate (4) leads to dihydropyrans 10 and 11, which after hydrogenation of the double bond as well as consecutive reduction of the nitro group and reductive amination give the desired forosamine‐type 2‐acetoxyamino sugars 21–24 and ossamine‐type 25.
The cover picture shows an analogue of the spinosyns, which are important, commercially used, natural insecticides for a broad variety of crops, such as corn and potatoes, since they are completely nontoxic to mammals with only minor effects on nontarget insects and fishes. A crucial aspect in the synthesis of these compounds and of analogues is the introduction of a β‐glycosidic bond with the amino sugar D‐forosamine, which is necessary for bioactivity. Details are discussed in the article by L. F. Tietze et al. on
White and prosocial lies are lies with socially harmless or benevolent motives or consequences. In ethical debate, these types of lie are controversial as ambivalent or even paradox concepts. The discussion of white and prosocial lies is based on the definition of lying in general, the status of untruthfulness, and the intent to deceive in particular. Three positions are distinguished: First, the absolute-moralist position advanced by Augustine and Kant, according to which the possibility of white or prosocial lies is completely rejected. Second, the utilitarian position, holding that lying might be justified in some cases of conflicting obligations, rights, or interests or because of its overall better consequences. Third, a neutral position that views lying as a conventional and morally neutral speech act. These approaches are discussed with respect to a number of crucial cases, and a taxonomy of white and prosocial lies is proposed.
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