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Although bisacetylenic oxylipins have been demonstrated to exhibit diverse biological activities, the chemical structures of many representatives of this class of phytochemicals still remain elusive. As carrots play an important role in our daily diet and are known as a source of bisacetylenes, an extract made from Daucus carota L. was screened for bisacetylenic oxylipins, and, after isolation, their structures were determined by means of LC-MS and 1D/2D NMR spectroscopy. Besides the previously reported falcarinol, falcarindiol, and falcarindiol 3-acetate, nine additional bisacetylenes were identified, among which six derivatives are reported for the first time in literature and three compounds were previously not identified in carrots. To determine the absolute stereochemistry of falcarindiol in carrots, the (3R,8R)-, (3R,8S)-, (3S,8R)-, and (3S,8S)-stereoisomers of falcarindiol were synthesized according to a novel 10-step total synthesis involving a Cadiot-Chodkiewicz cross-coupling reaction of (S)- and (R)-trimethylsilanyl-4-dodecen-1-yn-3-ol and (R)- and (S)-5-bromo-1-penten-4-yn-3-ol, respectively. Comparative chiral HPLC analysis of the synthetic stereoisomers with the isolated phytochemical led to the unequivocal assignment of the (Z)-(3R,8S)-configuration for falcarindiol in carrot extracts from Daucus carota L.

Dedicated to Professor Irina Petrovna BeletskayaThe catalytic addition of phosphines to alkenes (hydrophosphination) is an attractive process (Scheme 1). [1] It is a 100 % atom-economical reaction that uses widely available and inexpensive starting materials. It offers an access to alkylphosphines, which are useful ligands, [2] organocatalysts, [3] and reagents in organic synthesis. [4] However, due to the high energy of the P À H bond (E = 77 kcal mol À1 ), [5] the reaction usually requires activation by radical initiators. [1c, 6] Thermal-, [7] acid-, [8] and base-promoted [9] reactions have also been applied, although less frequently. Metal-and lanthanide-catalyzed processes were also reported recently. [1c, 10] Whatever the method, the addition usually proceeds in an anti-Markovnikov way leading to the b adduct B (addition of the phosphorus atom to the terminal carbon atom of a terminal alkene). In contrast, the selective formation of the [a] Dr.

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A flexible approach towards substituted β- and γ-carbolines based on transition metal catalysed [2+2+2] cycloaddition reactions between functionalised yne-ynamides and methylcyanoformate is described. The versatility of this new reaction sequence is demonstrated by its application in the total synthesis of the marine natural product eudistomin U.

The first total synthesis of the potent antioxidant antiostatin A1 is reported, where its key features rely on a chemo- and regioselective rhodium-catalysed crossed alkyne cyclotrimerisation reaction applying functionalised ynamides and a palladium-catalysed arylamidation reaction.

Copper-phosphido-borane complexes were synthesized and isolated for the first time. Their structures were experimentally and computationally investigated. They were shown to display catalytic activity in C(sp)-P bond formation.

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