D型葡萄糖和L型葡萄糖的旋光性結(jié)構(gòu)性能特點
來源：http://la-lin.cn 日期：2019-06-12 發(fā)布人：admin
1． 葡萄糖的旋光性和開鏈構(gòu)造式
1. Optical Rotation and Open Chain Constructions of Glucose
葡萄糖和絕大多數(shù)糖類均具有旋光性,可使平面偏振光發(fā)作旋轉(zhuǎn).若向右旋轉(zhuǎn),常用（＋）表示,向左旋轉(zhuǎn),常用（－）來表示.
Glucose and most sugars have optical rotation, which can make the plane polarized light rotate. If it rotates to the right, it is usually expressed as (+) or left, and it is often expressed as (-).
【平面偏振光】
[Planar Polarized Light]
【有關(guān)偏振光與旋光性的材料】
[Material relating to polarized light and optical rotation]
構(gòu)型：是指分子內(nèi)部手性碳原子所連結(jié)的原子或基團在空間排布的相對位置.葡萄糖的分子式為C6H12O6.【 D-（＋）-葡萄糖構(gòu)造式】
Configuration: The relative position of the atoms or groups connected by chiral carbon atoms in a molecule. The molecular formula of glucose is C6H12O6. [D-(+) - glucose structure]
命名準繩：將-CHO的碳原子定為一個碳原子,其它依次標示.從葡萄糖的開鏈構(gòu)造式中能夠看出C2、C3、C4、C5均為手性碳原子.由于在手性碳原子上銜接的原子或基團,它們在空間的位置是相對固定的,故寫構(gòu)造式時不能隨意更動.如在葡萄糖分子中C3上的一OH在左邊,C2、C4、C5上的一0H均在右邊.
Naming criterion: The carbon atom of -CHO is defined as the first carbon atom, and the others are labeled in turn. From the open-chain structure of glucose, we can see that C2, C3, C4 and C5 are all chiral carbon atoms. Because the atoms or groups connected on the chiral carbon atoms are relatively fixed in space, they can not be changed at will when writing the construction. For example, the OH on C3 in the glucose molecule is on the left, C2, C4. The 10H on C5 is on the right.
為了決議單糖的構(gòu)型,能夠甘油醛為規(guī)范.假如在投影式中,末了第2個碳原子（即己糖分子中的第5個碳原子）上的羥基在右邊,與D-（＋）-甘油醛相同,為D構(gòu)型；羥基在左邊,與L-（-）-甘油醛相同的為L構(gòu)型.
In order to determine the configuration of monosaccharides, glyceraldehyde can be used as a standard. If in the projection formula, the hydroxyl group on the last second carbon atom (the fifth carbon atom in the hexose molecule) is on the right side, the same as D-(+)-glyceraldehyde, and the hydroxyl group is on the left side, the same as L-(-)-glyceraldehyde.
實考證明自然存在的葡萄糖為右旋,屬于D構(gòu)型,所以應(yīng)寫成D-（＋）-葡萄糖.葡萄糖具有旋光性,其它大多數(shù)單糖分子也具旋光性.
It has been proved that the natural glucose is dextral and belongs to D configuration, so it should be written as D-(+) - glucose. Glucose has optical rotation, and most other monosaccharide molecules also have optical rotation.
2． 葡萄糖的環(huán)狀平面構(gòu)造式
2. The Ring Plane Formula of Glucose
由于碳原子的四個價鍵均勻散布于空間,因而葡萄糖的碳鏈實踐上并不是一條直線.葡萄糖的C1上醛基的氧原子和C5上的羥基在空間位置比擬靠近,在分子內(nèi)發(fā)作醛和醇的半縮醛反響,經(jīng)過氧橋構(gòu)成一個環(huán)狀構(gòu)造的半縮醛.葡萄糖分子內(nèi)發(fā)作的半縮醛反響使一碳原子也變成不對稱碳原子,這個碳原子上的羥基稱半縮醛羥基.半縮醛羥基在右邊的稱α-D-葡萄糖；半縮醛羥基在左邊的稱β-D-葡萄糖.葡萄糖的兩種環(huán)狀構(gòu)造都是右旋的,故它們的全名分別稱α-D-（＋）-葡萄糖和β-D-（＋）葡萄糖.
Since the four valence bonds of carbon atoms are evenly distributed in space, the carbon chain of glucose is not a straight line in practice. Oxygen atoms of aldehyde group on C1 and hydroxyl groups on C5 of glucose are comparatively close in space, and reactions of aldehydes and alcohols occur in molecules, forming a cyclic hemiacetal through oxygen bridge. The first carbon atom is also changed by reactions of aldehydes in glucose molecules. The hydroxyl groups on the carbon atoms are called semiacetal hydroxyl groups. The hydroxyl groups on the right side are called alpha-D-glucose; the hydroxyl groups on the left side are called beta-D-glucose. The two ring structures of glucose are dextral, so their full names are alpha-D-(+) -glucose and beta-D-(+) glucose, respectively.
【α-D-（＋）-葡萄糖】 【D-（＋）-葡萄糖】 【β-D-（＋）葡萄糖】
[alpha-D-(+) -glucose] [D-(+) -glucose] [beta-D-(+) glucose]