Heptoses

Heptoses are monosaccharides with a carbon backbone containing seven carbon atoms. They all have the empirical formula C ₇ H ₁₄ O ₇ and a molar mass of 210.18 g / mol. They differ in the type of carbonyl function. In the case of a keto group, one speaks of ketoheptoses , in the case of an aldehyde group it is called aldoheptoses . There are 32 stereoisomeric aldoheptoses and 16 stereoisomeric ketoheptoses.

Occurrence and use

Avocado fruit

Heptoses only play a subordinate role in nature. The few naturally occurring heptoses include:

The D -Sedoheptulose , as sedoheptulose-7-phosphate as an intermediate of the pentose phosphate pathway occurs and much of the regeneration of the D -Ribulose in the Calvin cycle is involved. The 7-deoxy-sedoheptulose is as herbicide investigated.
The D -Manno-heptulose , in the avocado fruit occurs, and as hexokinase inhibitor is used. Oral or intravenous administration of D- mannoheptulose leads to a reduced release of insulin and thus prevents the blood sugar level from falling too quickly .
The D -Talo-heptulose , which can be extracted from the avocado fruit.
The D- Allo-heptulose , which can be obtained from the avocado plant.

In addition, some heptoses are components of lipopolysaccharides (LPS).

Structure of the main ketoheptoses

Structure of the main aldoheptoses

Physical Properties

	D -doheptulosis	D -Mannoheptulosis	D -Alloheptulosis	D -Taloheptulosis	D -Mannoheptosis	D -Glucoheptosis
Molecular formula	C ₇ H ₁₄ O ₇	C ₇ H ₁₄ O ₇	C ₇ H ₁₄ O ₇	C ₇ H ₁₄ O ₇	C ₇ H ₁₄ O ₇	C ₇ H ₁₄ O ₇
CAS number	3019-74-7	3615-44-9	7101-28-2	31297-62-8	7634-39-1	62475-58-5
PubChem	102926	12600
M.p. (° C)	100-102	151-152	130-132	135-137	145	180
Appearance	White dust	White dust	White dust	White dust	White dust	White dust

Individual evidence

↑ Stryer L. Biochemistry . 4th edition. Spektrum Akademischer Verlag, 2004, p. 447.
↑ E. Simon, G. Frenkel, PF Kraicer: Blockade of insulin secretion by mannoheptulose. In: Israel Journal of Medical Sciences. Vol. 8, No. 6, 1972, ISSN 0021-2180 , pp. 743-752.
↑ ^a ^b Ingvar Johansson, Nelson K. Richtmyer: The isolation of Both a talo-heptulose and to allo-heptulose from the avocado. In: Carbohydrate Research . Vol. 13, 1970, pp. 461-464, doi: 10.1016 / S0008-6215 (00) 80607-2 .
↑ ^a ^b Peter M. Collins (Ed.): Dictionary of Carbohydrates. With CD-ROM. 2nd Edition. Chapman & Hall / CRC Press, Boca Raton FL et al. 2006, ISBN 0-8493-3829-8 , p. 607.
↑ ^a ^b Peter M. Collins (Ed.): Dictionary of Carbohydrates. With CD-ROM. 2nd Edition. Chapman & Hall / CRC Press, Boca Raton FL et al. 2006, ISBN 0-8493-3829-8 , p. 609.
^ Joseph H. Roe, CS Hudson: Further Studies of the Physiological Availability of Heptoses. (PDF; 290 kB) In: The Journal of Biological Chemistry. Vol. 121, No. 1, 1937. pp. 37-43.
↑ Dennis R. Heldman, Daryl B. Lund (Ed.): Handbook of Food Engineering (= Food Science and Technology. Vol. 161). 2nd Edition. CRC Press, Boca Raton FL et al. 2006, ISBN 0-8247-5331-3 , p. 339 .

[Stryer-1] Stryer L. Biochemistry . 4th edition. Spektrum Akademischer Verlag, 2004, p. 447.

[Israel-2] E. Simon, G. Frenkel, PF Kraicer: Blockade of insulin secretion by mannoheptulose. In: Israel Journal of Medical Sciences. Vol. 8, No. 6, 1972, ISSN 0021-2180 , pp. 743-752.

[Carbohydrate_Research-1-3] Ingvar Johansson, Nelson K. Richtmyer: The isolation of Both a talo-heptulose and to allo-heptulose from the avocado. In: Carbohydrate Research . Vol. 13, 1970, pp. 461-464, doi: 10.1016 / S0008-6215 (00) 80607-2 .

[Collins607-4] Peter M. Collins (Ed.): Dictionary of Carbohydrates. With CD-ROM. 2nd Edition. Chapman & Hall / CRC Press, Boca Raton FL et al. 2006, ISBN 0-8493-3829-8 , p. 607.

[Collins609-5] Peter M. Collins (Ed.): Dictionary of Carbohydrates. With CD-ROM. 2nd Edition. Chapman & Hall / CRC Press, Boca Raton FL et al. 2006, ISBN 0-8493-3829-8 , p. 609.

[JOBC-1-6] Joseph H. Roe, CS Hudson: Further Studies of the Physiological Availability of Heptoses. (PDF; 290 kB) In: The Journal of Biological Chemistry. Vol. 121, No. 1, 1937. pp. 37-43.

[FoodEngineerng-7] Dennis R. Heldman, Daryl B. Lund (Ed.): Handbook of Food Engineering (= Food Science and Technology. Vol. 161). 2nd Edition. CRC Press, Boca Raton FL et al. 2006, ISBN 0-8247-5331-3 , p. 339 .