Small bioactive molecules are pre-requisite for any discovery discipline. Aware of the fact that bioactivity is not randomly dispersed in the vast chemical space, chemists have been developing hypothesis that can lead them to the islands of bioactivities. Natural products have always been a source of inspiration and their structural motifs provide biologically relevant starting points for library synthesis. In addition to that, Diversity Oriented Synthesis (DOS) and Biology Oriented Synthesis (BIOS) have emerged as tools to guide synthesis design and help enrich compound collections in biological activities. Coherent developments in chem- and bioinformatic tools and in organic synthesis methods targeting efficient generation of compound collections are required to identify interesting molecules that can be employed as chemical probes in chemical biology research and drug candidates in medicinal chemistry investigations.

A silver catalyzed and microwave assisted one-pot cascade synthesis provides efficient access to diverse alkaloid-inspired scaffold classes, and a concise and efficient total synthesis of homofascaplysin C and fascaplysin.

Indoloisoquinolines (III) and benzazepino[2,1‐a]isoquinolines (V) are obtained in good yields by a silver‐catalyzed cascade cyclization of acetylenic aldehydes (I).

In discovering the remarkable catalytic properties of BINOL-derived phosphoramidites (binoP-NR(2)), Dutch researchers recently achieved a long-awaited breakthrough in asymmetric catalysis. For the first time, easily accessible monodentate chiral P(III) ligands turned out to provide high enantioselectivities when used in rhodium-catalysed olefin hydrogenation. The simplest ligand representative of this family is MonoPhos, which can be made straightforwardly from BINOL and hexamethylphosphorous triamide. Since the first publication dealing with such catalysts (J. Am. Chem. Soc., 2000), a variety of binoP-NRR' ligands have been reported in which the amino group bears a functional substituent or a stereogenic centre. This critical review examines the impact of the presence of such a functionality in the amino group on catalytic olefin hydrogenation reactions.

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All four stereoisomers of 4-(4,5-dihydro-3H-dinaphtho-[2,1-c:1',2'-e]azepin-4-yl}dinaphtho[2,1-d:1',2'-f][1,3,2]dioxa- phosphepine have been prepared from (R or S)-1,1'-bi-naphthyl-2,2'-diyl chlorophosphite and the appropriate dinaphtho-azepine. When reacted with [Rh(1,5-cyclooctadiene)2]BF4, highly active catalysts for the hydrogenation of alpha-dehydroamino acid esters were obtained. The highest enantioselectivities (up to 99% ee) were achieved with the phosphoramidites having two chiral binaphthyl groups with opposite configurations. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).

Enantiopure, BINOL-derived diphosphoramidites built upon an achiral hydrazine spacer are efficient ligands for the hydrogenation of 2-(acetylamino)-3-(aryl)-propenoic methyl esters. The activity and enantioselectivity of the hydrazine derivatives were shown to be markedly influenced by the nature of the two NR substituents, symmetrical but bulky R groups leading to the best results. A diphosphosphoramidite obtained from (t)BuHNNH(t)Bu resulted in ee's as high as 95%. The present results contradict previous reports on "short" diphosphoramidites.

The present work illustrates that enantiopure BINOL-derived diphosphoramidite ligands with hydrazine spacers are good ligands for the rhodium-catalyzed hydrogenation of 2-acetylamino-3-arylpropenoic methyl esters. The substituents on the two hydrazine nitrogens have a large influence on the enantioselectivity of the reaction, with bulky symmetrical groups leading to the highest ee values.

Six chiral monodentate ligands combining a 1,3-dioxa-2-phosphacycloheptadinaphthyl moiety [(R)- or (S)-binoP] either with a phenylalanine- or with an alanine-derived fragment were synthesised. The new phosphoramidites are all relatively air stable. Related compounds in which the binoP moiety was replaced by a diphenylphosphanyl group were also prepared for comparison. The X-ray structures of two phosphoramidite complexes, cis-PtCl(2)[(R))-binoP-NMeR](2) [5, R = (R)-CH(CH(2)Ph)(CO(2)Me); 6, R = (S)-CH(CH(2)Ph)(CO(2)Me)], were determined by single X-ray analysis. In the solid state, both structures are nearly C2 symmetric, and the nitrogen atoms lies out of the coordination plane. Owing to the particular orientation of the benzyl groups in 6, the environment of the coordination sites occupied in this complex by the chlorine atoms is sterically more crowded than in 5. In the hydrogenation of 2-(acetylamino)-3-(aryl)propenoic methyl esters (aryl = 4-X-C(6)H(4), X = H, F, Cl; aryl = 3,4-Cl(2)C(6)H(3)), the alanine-derived phosphoramidites turned out to be ca. twice as active as the corresponding phenylalanine analogues. The highest ee's were observed with the phenylalanine derivatives, for example 92% in the hydrogenation of 2-(acetylamino)-3-(phenyl)propenoic methyl ester, by using (R)-binoP-NMe-(R)-CH(CH(2)Ph)(CO(2)Me). ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).