To install click the Add extension button. That's it.

The source code for the WIKI 2 extension is being checked by specialists of the Mozilla Foundation, Google, and Apple. You could also do it yourself at any point in time.

4,5
Kelly Slayton
Congratulations on this excellent venture… what a great idea!
Alexander Grigorievskiy
I use WIKI 2 every day and almost forgot how the original Wikipedia looks like.
Live Statistics
English Articles
Improved in 24 Hours
Added in 24 Hours
What we do. Every page goes through several hundred of perfecting techniques; in live mode. Quite the same Wikipedia. Just better.
.
Leo
Newton
Brights
Milds

From Wikipedia, the free encyclopedia

An sp2-hybridized carbon atom, with re and si faces

In stereochemistry, prochiral molecules are those that can be converted from achiral to chiral in a single step.[1][2] An achiral species which can be converted to a chiral in two steps is called proprochiral.[2]

If two identical substituents are attached to a sp3-hybridized atom, the descriptors pro-R and pro-S are used to distinguish between the two. Promoting the pro-R substituent to higher priority than the other identical substituent results in an R chirality center at the original sp3-hybridized atom, and analogously for the pro-S substituent.

A trigonal planar sp2-hybridized atom can be converted to a chiral center when a substituent is added to the re or si (from Latin rectus 'right', and sinister 'left') face of the molecule. A face is labeled re if, when looking at that face, the substituents at the trigonal atom are arranged in increasing Cahn-Ingold-Prelog priority order (1 to 2 to 3) in a clockwise order, and si if the priorities increase in anti-clockwise order; note that the designation of the resulting chiral center as S or R depends on the priority of the incoming group.[3][4]

The concept of prochirality is necessary for understanding some aspects of enzyme stereospecificity. Alexander Ogston[5] pointed out that when a symmetrical molecule is placed in an asymmetric environment, such as the surface of an enzyme, supposedly identically placed groups become distinguishable. In this way he showed that earlier exclusion of non-chiral citrate as a possible intermediate in the tricarboxylate cycle was mistaken.

YouTube Encyclopedic

  • 1/3
    Views:
    17 163
    13 694
    25 152
  • Prochirality Explained | Organic Chemistry I | Lesson 8.8 | Course Krackers
  • Prochirality
  • Prochirality

Transcription

References

  1. ^ John McMurry (2008). Organic Chemistry (6th ed.). Brooks/Cole. pp. 301–303.
  2. ^ a b IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "prochirality". doi:10.1351/goldbook.P04859
  3. ^ Anslyn E. V. & Dennis A. D. (2005). Modern Physical Organic Chemistry. UCS: United states of america. ISBN 9781891389313.
  4. ^ IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "Re, Si". doi:10.1351/goldbook.R05308
  5. ^ Ogston, A. G. (1948). "Interpretation of Experiments on Metabolic processes, using Isotopic Tracer Elements". Nature. 963 (4120): 963. Bibcode:1948Natur.162..963O. doi:10.1038/162963b0. PMID 18225319.
This page was last edited on 5 January 2023, at 09:34
Basis of this page is in Wikipedia. Text is available under the CC BY-SA 3.0 Unported License. Non-text media are available under their specified licenses. Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc. WIKI 2 is an independent company and has no affiliation with Wikimedia Foundation.