nicotinamiden.

Brit.

/ˌnɪkəˈtɪnəmʌɪd/,

/ˌnɪkəˈtiːnəmʌɪd/, U.S.

/ˌnɪkəˈtɪnəˌmaɪd/,

/ˌnɪkəˈtinəˌmaɪd/

Origin: Formed within English, by compounding. Etymons: nicotinic adj., amide n.

Etymology: < nicotin- (in nicotinic adj.) + amide n.

Biochemistry.

The amide of nicotinic acid, (C₅H₄N)CONH₂, which is interconvertible with nicotinic acid in living organisms, providing a source of vitamin B₃. Also called niacinamide.

ΘΚΠ

the world > matter > chemistry > organic chemistry > amides > [noun] > nicotinamide

nicotinamide1895

niacinamide1944

1895 Jrnl. Chem. Soc. 68 i. 391 On heating ethylic nicotinate with alcoholic ammonia..it is converted into nicotinamide, which melts at 121°.

1949 H. W. C. Vines Green's Man. Pathol. (ed. 17) v. 107 Aneurin, riboflavine, nicotinamide and probably vitamin K can be synthesised in the mammalian intestine.

1951 in M. McLuhan Mech. Bride 91/1 It is nicotinamide, an important component in the familiar Vitamin B Complex pill.

1968 R. Passmore & J. S. Robson Compan. Med. Stud. I. v. 14/2 In Great Britain, the U.S.A. and many other countries, nicotinamide must by law be added to white flour used for bread making.

1991 Consumers Digest Dec. 123/1 Nicotinamide..protects the insulin-creating cells in the pancreas from nitric acid produced by attacking immune cells.

Compounds

nicotinamide adenine dinucleotide n. a coenzyme that participates in tissue respiration and other metabolic reactions, acting as an electron acceptor (by the addition of a hydride ion to the pyridine ring of the nicotinamide) during the oxidation of a substrate, and producing a reduced form which is then oxidized in another reaction; abbreviated NAD (also as the oxidized form NAD⁺; as the reduced form NADH).

ΚΠ

1960 Science 25 Nov. 1549/2 To complete the scheme we should expect NAD for nicotinamide-adenine dinucleotide, thus: FMN, NMN, FAD, NAD.

1984 E. Holtzman & A. B. Novikoff Cells & Organelles (ed. 3) i. iii. 37 In four of the steps we are considering, two hydrogen atoms are removed from substrates; from these, two electrons and one proton are transferred to NAD (nicotinamide adenine dinucleotide), with an additional H⁺ being freed.

1997 New Scientist 20 Dec. 48/1 The enzymes which destroy ethanol and methanol need the assistance of two ‘helper’ substances. The first, nicotinamide adenine dinucleotide (NAD), is responsible for taking away the hydrogen atoms snipped out of ethanol and methanol.

This entry has been updated (OED Third Edition, September 2003; most recently modified version published online March 2022).

单词	nicotinamide
释义	nicotinamiden. Brit. /ˌnɪkəˈtɪnəmʌɪd/, /ˌnɪkəˈtiːnəmʌɪd/, U.S. /ˌnɪkəˈtɪnəˌmaɪd/, /ˌnɪkəˈtinəˌmaɪd/ Origin: Formed within English, by compounding. Etymons: nicotinic adj., amide n. Etymology: < nicotin- (in nicotinic adj.) + amide n. Biochemistry. The amide of nicotinic acid, (C₅H₄N)CONH₂, which is interconvertible with nicotinic acid in living organisms, providing a source of vitamin B₃. Also called niacinamide. ΘΚΠ the world > matter > chemistry > organic chemistry > amides > [noun] > nicotinamide nicotinamide1895 niacinamide1944 1895 Jrnl. Chem. Soc. 68 i. 391 On heating ethylic nicotinate with alcoholic ammonia..it is converted into nicotinamide, which melts at 121°. 1949 H. W. C. Vines Green's Man. Pathol. (ed. 17) v. 107 Aneurin, riboflavine, nicotinamide and probably vitamin K can be synthesised in the mammalian intestine. 1951 in M. McLuhan Mech. Bride 91/1 It is nicotinamide, an important component in the familiar Vitamin B Complex pill. 1968 R. Passmore & J. S. Robson Compan. Med. Stud. I. v. 14/2 In Great Britain, the U.S.A. and many other countries, nicotinamide must by law be added to white flour used for bread making. 1991 Consumers Digest Dec. 123/1 Nicotinamide..protects the insulin-creating cells in the pancreas from nitric acid produced by attacking immune cells. Compounds nicotinamide adenine dinucleotide n. a coenzyme that participates in tissue respiration and other metabolic reactions, acting as an electron acceptor (by the addition of a hydride ion to the pyridine ring of the nicotinamide) during the oxidation of a substrate, and producing a reduced form which is then oxidized in another reaction; abbreviated NAD (also as the oxidized form NAD⁺; as the reduced form NADH). ΚΠ 1960 Science 25 Nov. 1549/2 To complete the scheme we should expect NAD for nicotinamide-adenine dinucleotide, thus: FMN, NMN, FAD, NAD. 1984 E. Holtzman & A. B. Novikoff Cells & Organelles (ed. 3) i. iii. 37 In four of the steps we are considering, two hydrogen atoms are removed from substrates; from these, two electrons and one proton are transferred to NAD (nicotinamide adenine dinucleotide), with an additional H⁺ being freed. 1997 New Scientist 20 Dec. 48/1 The enzymes which destroy ethanol and methanol need the assistance of two ‘helper’ substances. The first, nicotinamide adenine dinucleotide (NAD), is responsible for taking away the hydrogen atoms snipped out of ethanol and methanol. This entry has been updated (OED Third Edition, September 2003; most recently modified version published online March 2022). < n.1895
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