Stereochemistry Endo Exo
Stereochemistry Endo Exo - Related Videos
07:46
Assessing Endothelial Vasodilator Function with the Endo-PAT 2000
0 Views •
Cited by 165 •
2010
A noninvasive procedure to assess endothelial function is demonstrated using the Endo-PAT 2000.
09:54
Identification and Characterization of Protein Glycosylation using Specific Endo- and Exoglycosidases
0 Views •
Cited by 31 •
2011
Using specific glycosidases to remove sugars from glycoproteins followed by SDS-PAGE is a valuable method to detect glycan modifications on protein samples and is a good choice for initial glycobiology studies. Changes following deglycosylation can be detected as shifts in gel mobility or by staining with glycan sensitive reagents.
02:58
Nanoparticle-Mediated Visualization of Endo-Lysosomal Remodeling in Bacterially-Infected Cells
0 Views •
2025
Source: Zhang, Y., et al. Application of Fluorescent Nanoparticles to Study Remodeling of the Endo-lysosomal System by Intracellular Bacteria. J. Vis. Exp. (2015)This video demonstrates the use of fluorescent nanoparticles to visualize endo-lysosomal remodeling in human epithelial cells infected by intracellular bacteria. Following bacterial invasion, the pathogens manipulate the host cytoskeleton and endo-lysosomal system, forming vacuoles with tubular projections that alter vesicle transport.
02:15
SN1 Reaction: Stereochemistry
0 Views •
2023
This lesson provides an in-depth discussion of the stereochemical outcomes in an SN1 reaction. In the first step of an SN1 reaction, the bond between the electrophilic carbon and the leaving group ionizes to generate the carbocation intermediate. The second step of the mechanism is the nucleophilic attack. In the formed carbocation, the positively charged carbon is sp2 hybridized with a trigonal planar geometry. As all the three substituents lie on the same plane, a plane of symmetry for the...
09:27
The ChIP-exo Method: Identifying Protein-DNA Interactions with Near Base Pair Precision
0 Views •
Cited by 9 •
2016
Here, we present a protocol to achieve near base pair resolution of protein-DNA interactions. This is obtained by exonuclease treatment of DNA fragments selectively enriched by chromatin immunoprecipitation (ChIP-exo) followed by high throughput sequencing.
FAQs
Secondary orbital interactions can stabilize the transition-state arrangement that leads to the endo product. This preference commonly appears under kinetic control, so the endo pathway may produce its product more rapidly even when another stereoisomer has greater thermodynamic favorability. The interaction therefore helps explain observed stereoselectivity rather than simply describing the final molecular geometry.
Kinetic control favors the product formed through the lower-energy or faster pathway, which often corresponds to the endo product in relevant Diels–Alder reactions. Thermodynamic control instead emphasizes relative product stability, allowing the exo product to become more favorable. Comparing these outcomes helps chemists connect reaction conditions with the stereoisomer actually obtained.
Assignment requires examining the three-dimensional arrangement of bonds in the bridged or bicyclic framework, not merely the two-dimensional drawing. The analyst determines how each substituent is oriented relative to the bridge or interior of the framework, then uses that spatial relationship to label the configuration. This approach is especially useful for norbornene derivatives.
Chemists first identify the bridge and the relevant substituents in the product structure, then inspect their relative spatial orientations. A three-dimensional representation or conformational analysis can clarify whether each group is directed toward the framework’s interior or away from it. The resulting assignment supports accurate product-structure analysis and comparison of stereoisomers.
This distinction is particularly useful when planning or analyzing Diels–Alder routes that generate bridged or bicyclic products. Predicting the likely stereochemical outcome helps chemists anticipate product structures and evaluate whether kinetic or thermodynamic control is relevant. It also supports the design of synthetic routes involving norbornene derivatives and related bridged frameworks.
Endo and exo analysis reveals the stereoselectivity of the reaction and identifies the relative arrangement of substituents in the product. By comparing the assigned configuration with the expected kinetic or thermodynamic preference, chemists can interpret the reaction outcome and refine structural assignments. In chemistry research, this provides a practical link between mechanism, conformation, and synthetic design.