Haworth, Sir Walter

HAWORTH. SIR WALTER N. 0883-1950). An English chemist who received the Nobel prize in chemistry in 1937 along with Paul Karrer. He recommended the name ascorbic acid and synthesized vitamin C, He accomplished much work on carbohydrate structure und developed a substitute for blood plasma using carbohydrates. During World War 11. he developed gaseous diffusion separation on uranium isotopes. He received his Ph D. in Manchester. England. 

Haworth, Sir Walter Norman (1883-1950) English chemist who was the first to establish the molecular structure of vitamin C and who named it ascorbic acid. Haworth shared the 1937 Nobel Prize in chemistry with Paul Karrer. 

Structural drawings of carbohydrates of this type are called Haworth formulas, after the British chemist Sir Walter Norman Haworth (St Andrew s University and the University of Birmingham) Early m his career Haworth contributed to the discovery that carbohydrates exist as cyclic hemiacetals rather than m open chain forms Later he col laborated on an efficient synthesis of vitamin C from carbohydrate precursors This was the first chemical synthesis of a vitamin and provided an inexpensive route to its prepa ration on a commercial scale Haworth was a corecipient of the Nobel Prize for chem istry m 1937... 

Using methods similar to Fischer s, the straight-chain form of any monosaccharide can be worked out. As we have seen, however, monosaccharides exist mostly as cyclic pyra-nose or furanose hemiacetals. These hemiacetals are in equilibrium with the open-chain forms, so sugars can react like hemiacetals or like ketones and aldehydes. How can we freeze this equilibrium and determine the optimum ring size for any given sugar Sir Walter Haworth (inventor of the Haworth projection) used some simple chemistry to determine the pyranose structure of glucose in 1926. 

Widespread Mabis (apple), Rosa (rose hip) (Rosaceae), Citrus (Rutaceae), Capsicum (Szegedi paprika) (Solanaceae) spp. Vitamin C reaches 20-300 mM in chloroplasts discovered by Albert Szent-Gyorgyi (Hungary/ USA, Nobel Prize, 1937 [vitamin C biological oxidations]) structure synthesis (Sir Walter Haworth (UK, Nobel Prize, Chemistry, 1937, [carbohydrates vitamin C]) identified by W.A. Waugh C.G. King (USA)... 

Stamps issued in honor of English Nobel laureates (a) Sir Derek Barton for conformational analysis, 1969 (b) Sir Walter Haworth for the synthesis of vitamin C, 1937 (c) A. J. P. Martin and Richard L. M. Synge for chromatography, 1952 ... 

In the early part of the twentieth century, extensive efforts were undertaken by, among others, Sir Walter Norman ffaworth to affect the synthesis of the carbohydrate vitamin C, which had been long recognized as necessary to avoid scurvy by British seamen. The Haworth synthesis (that barely preceded that of Reichstein, vide infra) is provided as Scheme 11.16. 

Sir Walter Norman Haworth (1883-1950), professor and department head, University of Birmingham, Nobel Prize 1937, Chemistry, shared with Professor Paul Karrer (about whom more later). The Nobel Prize in Chemistry 1937 was divided equally between Walter Norman Haworth for his investigations on carbohydrates and vitamin C and Paul Karrer for his investigations on carotenoids, flavins, and vitamins A and 82-... 

Another ubiquitous earthly material is the class of carbohydrates. They have been important to human civilization from the beginning. The understanding of the nature and stmcture of pure polysaccharides came relatively late in the prehistory of polymer science, but the first Nobel Prize associated with macromolecules was awarded to Sir Walter Norman Haworth in 1937. 

The earth is filled with polysaccharides. They have impacted human culture since the beginning. The growth in understanding of this class of macromolecules was slow, but the first Nobel Prize in Chemistry that was awarded for work that specifically included polymers was given to Sir Walter Norman Haworth (1883-1950, FRS) in 1937 for his work on polysaccharides. These materials constitute one of the most fascinating groups of macromolecules (Fig. 2.12). 

Fig. 2.12 Sir Walter Norman Haworth (1883-1950, Nobel 1937) (Nobel Archives)...

Another center of textile fibre science was Birmingham and Sir Walter Norman Haworth (1883-1950, FRS, Nobel 1937) presented a very detailed report on the primary valence chains of several polysaccharides. Cellulose was shown by direct chemical analysis to contain from 100 to 200 subunits in a linear chain. Starch was analyzed in a similar fashion and found to be from 24 to 30 glucopyranose units. Glycogen is even shorter(12 units). The fundamentally different substance, inulin, is a fructofuranose of approximately 30 units. Macromolecules are envisioned in a fully modern sense in this paper. The three dimensional aspects were also addressed, since 1,4-glucose linkages produced different chains than 1,2-furanose linkages. 

In 1928, the Hungarian biochemist Albert Szent-Gyorgyi isolated vitamin C, which was first designated as hexuronic acid, from the adrenal glands of animals and later from Hungarian paprika peppers. Between 1933 and 1934, the British chemists Sir Walter Norman Haworth and Sir Edmund Hirst and the Polish-Swiss chemist Tadeusz Reichstein succeeded in synthesizing vitamin C. The Reichstein process was adopted by F. Hoffmann-La Roche to produce vitamin C from 1934. The process includes one microbial oxidation step, from o-sorbitol to L-sorbose, and has been used commercially for about 80 years with many chemical and technical modifications to improve the efficiency of each step (Fig. 15.1). Currently more than 100,000 tons per year of pure vitamin C are produced worldwide. 

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