Department of Medicine, University of Colorado School of Medicine, Aurora, Colorado, USA.
Chirality. 2011 Sep;23(8):647-59. doi: 10.1002/chir.20955. Epub 2011 Jul 13.
Asymmetric objects are necessarily chiral, but a structure may be chiral and not asymmetric if it possesses one or more proper rotation axes. Chiral but not asymmetric molecules are important in chemistry and its applications, but no suitable term exists for the designation of such structures, and their terminology in the literature is confused and chaotic. Dissymmetric has been redefined by some authors as "chiral but not asymmetric," in conflict both with Pasteur's definition of the term as "not superposable on its mirror image" (without other restrictions, i.e., chiral) and the understanding of the term in stereochemistry. Moreover, dissymmetric and asymmetric are frequently confused because of their similar forms. Furthermore, dissymmetric is widely used in many other definitions in chemistry, physics, and other disciplines. Thus, dissymmetric is unsuitable in the new definition of "chiral but not asymmetric," and a new term is needed. The adjective "symmanumorphous" is therefore proposed for "chiral but not asymmetric". "Sym" (from symmetry) indicates the presence of some symmetry in the structure, and "manu" (from "manus," Latin for hand, e.g., manual, manuscript) refers to its handedness. "Morphous," from the Greek "morphē," that is, form, is widely used, for example, anthropomorphous, enantiomorphous, etc. Symmanumorphous is convenient and euphonious and at 15 characters (same as enantiomorphous) is not unduly long. The nouns "a symmanumorph" (a structure that is chiral but not asymmetric) and "symmanumorphism" (the phenomenon of chirality without asymmetry) are also proposed. The new terminology is adaptable in other languages and would contribute to creating order out of linguistic chaos.
不对称的物体必然是手性的，但如果一个结构具有一个或多个正当旋转轴，它可能是手性的而不是不对称的。手性但不对称的分子在化学及其应用中很重要，但没有合适的术语来指定这种结构，其在文献中的术语是混乱和混乱的。一些作者将“不对称”重新定义为“手性但不对称”，这与巴斯德将该术语定义为“不能与其镜像重叠”（没有其他限制，即手性）以及立体化学中对手性的理解相矛盾。此外，由于它们的相似形式，不对称和不对称经常混淆。此外，不对称在化学、物理和其他学科的许多其他定义中被广泛使用。因此，不对称在手性但不对称的新定义中不合适，需要一个新术语。因此，提出形容词“symmanumorphous”来表示“手性但不对称”。“Sym”（来自对称性）表示结构中存在一些对称性，而“manu”（来自拉丁语“手”，例如，manual，manuscript）表示其手性。“Morphous”来自希腊语“morphē”，即形式，被广泛使用，例如，anthropomorphous，enantiomorphous 等。Symmanumorphous 既方便又悦耳，而且有 15 个字符（与 enantiomorphous 相同），也不算太长。还提出了名词“a symmanumorph”（一个手性但不对称的结构）和“symmanumorphism”（没有不对称的手性现象）。新术语在其他语言中也具有适应性，并有助于消除语言混乱。
