498 research outputs found
Understanding plyometrics: A coach's guide
The popularity of plyometric exercises highlights the critical role that they play in developing athletes within strength and conditioning practices. However, although a staple exercise of the strength and conditioning practitioner’s toolbox, plyometrics are all too often overlooked, resulting in practitioners not reaping the most benefits from their application. This article attempts to provide more clarity and guidance towards the use of plyometrics with the aim of improving practitioner application and understanding. This includes building a greater understanding of plyometric adaptations, as well as an awareness of movement strategy, exercise prescription and exercise progressions
The stereospecificity of alcohol oxidases from Tanacetum Vulgare and Candida Boidinii
The stereospecificity of the oxidation of trans-hex-2-en-1-ol and ethanol was determined for alcohol oxidases from leaves and from the yeast . It was found that both enzymes remove the pro-1R hydrogen. The enzyme from also removes the pro-1S hydrogen but to a much lesser degree.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/21943/1/0000350.pd
Reactions of Azides with Electrophiles: New Methods for the Generation of Cationic 2‐Azabutadienes. Synthesis of 1,2, 3,4‐Tetrahydroquinolines and 1,2‐Dihydroquinolines via a Hetero Diels–Alder Reaction
Two methods for the generation of iminium ions of the type ArN + (X)=CHR (X = H or alkyl, R = H or alkyl) are reported: (1) the Bronsted‐acid‐promoted rearrangement of benzylic azides and (2) the intermolecular Schmidt reactions of azides XN 3 (X = aliphatic) with benzylic carbocations derived from benzylic alcohols ArCH(R)OH. The iminium ions ArN + (X)=CHR behave as cationic 2‐azabutadienes in the presence of alkenes and alkynes, producing 1,2, 3,4‐tetrahydroquinolines and 1,2‐dihydroquinolines by a hetero Diels–Alder reaction.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/101768/1/199700007_ftp.pd
Enantiomere Naturstoffe: Vorkommen und Biogenese
In der Natur werden chirale Substanzen meist in enantiomerenreiner Form synthetisiert – manchmal entstehen aber auch beide Enantiomere. Solche enantiomeren Naturstoffe können von einer Art oder von verschiedenen Gattungen und/oder Arten gebildet werden. Intensive Forschungen wurden über viele Jahre durchgeführt, um die Biogenese natürlich vorkommender Enantiomere zu verstehen, doch viele faszinierende Rätsel und stereochemische Anomalien sind nach wie vor ungelöst. Bild und Spiegelbild in der Natur: Die Bildung von natürlich vorkommenden Enantiomerenpaaren ist bekannt, wenn auch selten (siehe Beispiel). Bis heute sind noch viele Rätsel und stereochemische Anomalien bei der Biogenese dieser einmaligen Naturstoffe ungelöst, auch wenn im Laufe der Jahre viel Arbeit investiert worden ist, um die Entstehung enantiomerer Metaboliten zu verstehen.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91315/1/4886_ftp.pd
Enantiomeric Natural Products: Occurrence and Biogenesis
In nature, chiral natural products are usually produced in optically pure form—however, occasionally both enantiomers are formed. These enantiomeric natural products can arise from a single species or from different genera and/or species. Extensive research has been carried out over the years in an attempt to understand the biogenesis of naturally occurring enantiomers; however, many fascinating puzzles and stereochemical anomalies still remain. Two sides to the story : The formation of enantiomerically opposite natural products by nature is known, although rare (see examples). To date, many puzzles and stereochemical anomalies remain regarding the biogenesis of these unique natural products, despite the substantial body of research that has been carried out over the years in an attempt to understand the biogenesis of enantiomeric metabolites.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/92098/1/4802_ftp.pd
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