1648:
632:
650:
360:
312:
534:
516:
378:
550:
500:
426:
410:
344:
328:
394:
130:
Like some other monosaccharides, pentoses exist in two forms, open-chain (linear) or closed-chain (cyclic), that easily convert into each other in water solutions. The linear form of a pentose, which usually exists only in solutions, has an open-chain backbone of five carbons. Four of these
610:, which may have any of two configurations, depending on the position of the new hydroxyl. Therefore, each linear form can produce two distinct closed forms, identified by prefixes "α" and "β".
492:
The 2-ketopentoses have two chiral centers; therefore, four (2) different stereoisomers are possible. The 3-ketopentoses are rare.
912:
592:
molecule, with a ring consisting of one oxygen atom and usually four carbon atoms; the cyclic compounds are then called
851:
211:
that can be described as derived from pentoses by replacement of one or more hydroxyl groups with hydrogen atoms.
878:
699:
The most important tests for pentoses rely on converting the pentose to furfural, which then reacts with a
905:
459:
104:
223:
are a subclass of the pentoses which, in the linear form, have the carbonyl at carbon 1, forming an
972:
255:–H (3-ketopentose). The latter is not known to occur in nature and are difficult to synthesize.
1465:
585:
1651:
1459:
898:
802:
868:
841:
1453:
471:
120:
1592:
724:
262:
that differ in the spatial position of the hydroxyl groups. These forms occur in pairs of
8:
708:
475:
463:
108:
735:. In each of these tests, pentoses react much more strongly and quickly than hexoses.
1672:
874:
847:
822:
764:
751:
1045:
814:
704:
279:
135:
73:
39:
1494:
1440:
1420:
1311:
600:
589:
100:
1481:
1278:
1035:
1012:
992:
728:
720:
712:
573:
263:
28:
1666:
1587:
1504:
1392:
1283:
826:
818:
659:
297:
139:
1471:
1352:
1334:
982:
922:
607:
301:
259:
116:
80:
146:
group (C=O). The remaining bonds of the carbon atoms are satisfied by six
1629:
1617:
1489:
1400:
1148:
1143:
1083:
890:
840:
Seager, Spencer L.; Slabaugh, Michael R.; Hansen, Maren S. (2016-12-05).
784:
700:
641:
619:
581:
451:
236:
220:
175:
124:
92:
580:
in another carbon, turning the carbonyl into a hydroxyl and creating an
258:
In the open form, there are eight aldopentoses and four 2-ketopentoses,
142:, and one has an oxygen atom connected by a double bond (=O), forming a
1405:
1347:
1342:
1215:
1168:
467:
112:
649:
631:
1563:
1559:
1514:
1428:
1410:
1377:
1362:
1183:
1106:
1068:
870:
Introduction to
Organic Laboratory Techniques: A Small Scale Approach
673:
387:
321:
20:
1580:
1541:
1526:
1499:
1448:
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1255:
1250:
1235:
1220:
1136:
1131:
951:
946:
716:
688:
593:
577:
559:
543:
525:
509:
224:
147:
143:
132:
1622:
1602:
1570:
1545:
1535:
1531:
1509:
1372:
1367:
1357:
1267:
1230:
1225:
1203:
1188:
1178:
1073:
1057:
732:
684:
359:
1612:
1607:
1597:
1574:
1551:
1519:
1306:
1301:
1245:
1208:
1193:
1173:
1160:
1121:
1116:
1111:
1024:
977:
967:
941:
936:
677:
487:
443:
435:
419:
403:
369:
353:
337:
291:
240:
232:
84:
32:
311:
1198:
1001:
597:
533:
515:
377:
572:
The closed or cyclic form of a pentose is created when the
549:
499:
425:
409:
343:
327:
35:
455:
447:
393:
239:
instead have the carbonyl at positions 2 or 3, forming a
150:
atoms. Thus the structure of the linear form is H–(CHOH)
96:
88:
458:. Phosphorylated pentoses are important products of the
772:". PubChem compound webpage, accessed on 2010-02-06.
839:
170:The term "pentose" sometimes is assumed to include
624:The one deoxypentose has two total stereoisomers.
123:(E4P), which is used in the synthesis of aromatic
785:Morrison, Robert Thornton; Boyd, Robert Neilson.
1664:
278:" by conventional rules (independently of their
803:"Ueber Spectral‐Reactionen des Methylfurfurols"
757:
807:Berichte der Deutschen Chemischen Gesellschaft
906:
800:
707:’ test for pentoses (not to be confused with
606:The closure turns the carboxyl carbon into a
243:derivative with structure H–CHOH–C(=O)–(CHOH)
920:
913:
899:
801:Oshima, Kintaro; Tollens, B. (May 1901).
474:(E4P), which is used in the synthesis of
466:(R5P), which is used in the synthesis of
111:(R5P), which is used in the synthesis of
227:derivative with structure H–C(=O)–(CHOH)
687:composed of pentose sugars is called a
103:pentoses are important products of the
1665:
723:to produce a colored compound; in the
894:
866:
780:
778:
694:
791:Library of Congress catalog 66-25695
672:In the cell, pentoses have a higher
843:Safety Scale Laboratory Experiments
596:, for having the same rings as the
584:–O– between the two carbons. This
231:–H. The most important example is
13:
775:
138:(–OH) each, connected by a single
14:
1684:
873:. Cengage Learning. p. 447.
846:. Cengage Learning. p. 358.
300:; therefore, eight (2) different
214:
178:: compounds with general formula
1647:
1646:
789:(2nd ed.). Allyn and Bacon.
648:
630:
613:
548:
532:
514:
498:
424:
408:
392:
376:
358:
342:
326:
310:
481:
285:
79:Pentoses are very important in
860:
833:
794:
745:
567:
247:–H (2-ketopentose) or H–(CHOH)
1:
738:
727:with aniline acetate; and in
667:
646:
628:
530:
496:
450:, and the related molecule,
374:
308:
296:The aldopentoses have three
91:, and the related molecule,
7:
709:Tollens' silver-mirror test
10:
1689:
617:
485:
289:
1642:
1480:
1437:
1419:
1391:
1333:
1326:
1294:
1266:
1159:
1094:
1056:
1023:
1000:
991:
960:
929:
867:Pavia, Donald L. (2005).
460:pentose phosphate pathway
105:pentose phosphate pathway
31:(simple sugar) with five
973:Cyclohexane conformation
819:10.1002/cber.19010340212
1466:Isomaltooligosaccharide
586:intramolecular reaction
470:and nucleic acids, and
1460:Galactooligosaccharide
454:, is a constituent of
266:, generally labelled "
95:, is a constituent of
1454:Fructooligosaccharide
472:erythrose 4-phosphate
121:erythrose 4-phosphate
16:5-Carbon simple sugar
725:aniline acetate test
476:aromatic amino acids
446:is a constituent of
87:is a constituent of
42:of many pentoses is
462:, most importantly
107:, most importantly
695:Tests for pentoses
464:ribose 5-phosphate
109:ribose 5-phosphate
1660:
1659:
1638:
1637:
1322:
1321:
787:Organic Chemistry
754:, Merriam-Webster
719:ring reacts with
665:
664:
657:
639:
576:interacts with a
565:
564:
557:
541:
523:
507:
441:
440:
433:
417:
401:
385:
367:
351:
335:
319:
131:carbons have one
76:is 150.13 g/mol.
1680:
1650:
1649:
1441:oligosaccharides
1421:Tetrasaccharides
1331:
1330:
1046:Dihydroxyacetone
998:
997:
915:
908:
901:
892:
891:
885:
884:
864:
858:
857:
837:
831:
830:
813:(2): 1425–1426.
798:
792:
790:
782:
773:
769:
768:
761:
755:
749:
655:
652:
637:
634:
627:
626:
555:
552:
539:
536:
521:
518:
505:
502:
495:
494:
431:
428:
415:
412:
399:
396:
383:
380:
365:
362:
349:
346:
333:
330:
317:
314:
307:
306:
280:optical activity
277:
276:
271:
270:
210:
209:
208:
197:
196:
188:
187:
136:functional group
74:molecular weight
71:
70:
69:
61:
60:
52:
51:
40:chemical formula
1688:
1687:
1683:
1682:
1681:
1679:
1678:
1677:
1663:
1662:
1661:
1656:
1634:
1495:Oat beta-glucan
1482:Polysaccharides
1476:
1439:
1433:
1415:
1387:
1318:
1312:Neuraminic acid
1290:
1262:
1155:
1090:
1052:
1019:
993:Monosaccharides
987:
956:
925:
919:
889:
888:
881:
865:
861:
854:
838:
834:
799:
795:
783:
776:
766:
765:
762:
758:
750:
746:
741:
713:reducing sugars
697:
676:stability than
670:
654:
653:
636:
635:
622:
616:
601:tetrahydrofuran
570:
554:
553:
538:
537:
520:
519:
504:
503:
490:
484:
430:
429:
414:
413:
398:
397:
382:
381:
364:
363:
348:
347:
332:
331:
316:
315:
294:
288:
274:
273:
268:
267:
264:optical isomers
254:
250:
246:
230:
217:
207:
201:
200:
199:
195:
192:
191:
190:
186:
183:
182:
181:
179:
167:is 0, 1, or 2.
162:
155:
68:
65:
64:
63:
59:
56:
55:
54:
50:
47:
46:
45:
43:
17:
12:
11:
5:
1686:
1676:
1675:
1658:
1657:
1655:
1654:
1643:
1640:
1639:
1636:
1635:
1633:
1632:
1627:
1626:
1625:
1620:
1610:
1605:
1600:
1595:
1593:Levan beta 2→6
1590:
1585:
1584:
1583:
1567:
1556:
1555:
1554:
1538:
1529:
1524:
1523:
1522:
1517:
1512:
1507:
1502:
1497:
1486:
1484:
1478:
1477:
1475:
1474:
1469:
1463:
1457:
1451:
1445:
1443:
1435:
1434:
1432:
1431:
1425:
1423:
1417:
1416:
1414:
1413:
1408:
1403:
1397:
1395:
1393:Trisaccharides
1389:
1388:
1386:
1385:
1380:
1375:
1370:
1365:
1360:
1355:
1350:
1345:
1339:
1337:
1328:
1324:
1323:
1320:
1319:
1317:
1316:
1315:
1314:
1304:
1298:
1296:
1292:
1291:
1289:
1288:
1287:
1286:
1281:
1279:Mannoheptulose
1272:
1270:
1264:
1263:
1261:
1260:
1259:
1258:
1253:
1248:
1240:
1239:
1238:
1233:
1228:
1223:
1213:
1212:
1211:
1206:
1201:
1196:
1191:
1186:
1181:
1176:
1165:
1163:
1157:
1156:
1154:
1153:
1152:
1151:
1141:
1140:
1139:
1134:
1126:
1125:
1124:
1119:
1114:
1109:
1100:
1098:
1092:
1091:
1089:
1088:
1087:
1086:
1078:
1077:
1076:
1071:
1062:
1060:
1054:
1053:
1051:
1050:
1049:
1048:
1040:
1039:
1038:
1036:Glyceraldehyde
1029:
1027:
1021:
1020:
1018:
1017:
1016:
1015:
1013:Glycolaldehyde
1006:
1004:
995:
989:
988:
986:
985:
980:
975:
970:
964:
962:
958:
957:
955:
954:
949:
944:
939:
933:
931:
927:
926:
918:
917:
910:
903:
895:
887:
886:
879:
859:
852:
832:
793:
774:
756:
743:
742:
740:
737:
721:phloroglucinol
696:
693:
669:
666:
663:
662:
645:
644:
615:
612:
574:carbonyl group
569:
566:
563:
562:
546:
529:
528:
512:
483:
480:
439:
438:
422:
406:
390:
373:
372:
356:
340:
324:
304:are possible.
298:chiral centers
287:
284:
252:
248:
244:
228:
216:
215:Classification
213:
202:
193:
184:
157:
151:
101:Phosphorylated
66:
57:
48:
29:monosaccharide
15:
9:
6:
4:
3:
2:
1685:
1674:
1671:
1670:
1668:
1653:
1645:
1644:
1641:
1631:
1628:
1624:
1621:
1619:
1616:
1615:
1614:
1611:
1609:
1606:
1604:
1601:
1599:
1596:
1594:
1591:
1589:
1588:Hemicellulose
1586:
1582:
1579:
1578:
1577:
1576:
1572:
1568:
1566:
1565:
1561:
1557:
1553:
1550:
1549:
1548:
1547:
1543:
1539:
1537:
1533:
1530:
1528:
1525:
1521:
1518:
1516:
1513:
1511:
1508:
1506:
1503:
1501:
1498:
1496:
1493:
1492:
1491:
1488:
1487:
1485:
1483:
1479:
1473:
1470:
1467:
1464:
1461:
1458:
1455:
1452:
1450:
1447:
1446:
1444:
1442:
1436:
1430:
1427:
1426:
1424:
1422:
1418:
1412:
1409:
1407:
1404:
1402:
1399:
1398:
1396:
1394:
1390:
1384:
1381:
1379:
1376:
1374:
1371:
1369:
1366:
1364:
1361:
1359:
1356:
1354:
1351:
1349:
1346:
1344:
1341:
1340:
1338:
1336:
1335:Disaccharides
1332:
1329:
1325:
1313:
1310:
1309:
1308:
1305:
1303:
1300:
1299:
1297:
1293:
1285:
1284:Sedoheptulose
1282:
1280:
1277:
1276:
1275:Ketoheptoses
1274:
1273:
1271:
1269:
1265:
1257:
1254:
1252:
1249:
1247:
1244:
1243:
1242:Deoxy sugars
1241:
1237:
1234:
1232:
1229:
1227:
1224:
1222:
1219:
1218:
1217:
1214:
1210:
1207:
1205:
1202:
1200:
1197:
1195:
1192:
1190:
1187:
1185:
1182:
1180:
1177:
1175:
1172:
1171:
1170:
1167:
1166:
1164:
1162:
1158:
1150:
1147:
1146:
1145:
1142:
1138:
1135:
1133:
1130:
1129:
1128:Ketopentoses
1127:
1123:
1120:
1118:
1115:
1113:
1110:
1108:
1105:
1104:
1103:Aldopentoses
1102:
1101:
1099:
1097:
1093:
1085:
1082:
1081:
1079:
1075:
1072:
1070:
1067:
1066:
1065:Aldotetroses
1064:
1063:
1061:
1059:
1055:
1047:
1044:
1043:
1041:
1037:
1034:
1033:
1031:
1030:
1028:
1026:
1022:
1014:
1011:
1010:
1008:
1007:
1005:
1003:
999:
996:
994:
990:
984:
981:
979:
976:
974:
971:
969:
966:
965:
963:
959:
953:
950:
948:
945:
943:
940:
938:
935:
934:
932:
928:
924:
923:carbohydrates
916:
911:
909:
904:
902:
897:
896:
893:
882:
876:
872:
871:
863:
855:
853:9781337517140
849:
845:
844:
836:
828:
824:
820:
816:
812:
808:
804:
797:
788:
781:
779:
771:
760:
753:
748:
744:
736:
734:
730:
726:
722:
718:
714:
710:
706:
702:
692:
690:
686:
681:
679:
675:
661:
651:
647:
643:
633:
629:
625:
621:
614:Deoxypentoses
611:
609:
608:chiral center
604:
602:
599:
595:
591:
587:
583:
579:
575:
561:
551:
547:
545:
535:
531:
527:
517:
513:
511:
501:
497:
493:
489:
479:
477:
473:
469:
465:
461:
457:
453:
449:
445:
437:
427:
423:
421:
411:
407:
405:
395:
391:
389:
379:
375:
371:
361:
357:
355:
345:
341:
339:
329:
325:
323:
313:
309:
305:
303:
302:stereoisomers
299:
293:
283:
281:
265:
261:
260:stereoisomers
256:
251:–C(=O)–(CHOH)
242:
238:
234:
226:
222:
212:
206:
177:
173:
172:deoxypentoses
168:
166:
161:
156:–C(=O)–(CHOH)
154:
149:
145:
141:
137:
134:
128:
126:
122:
118:
117:nucleic acids
114:
110:
106:
102:
98:
94:
90:
86:
82:
77:
75:
41:
37:
34:
30:
26:
22:
1569:
1558:
1540:
1472:Maltodextrin
1353:Isomaltulose
1144:Deoxy sugars
1095:
1080:Ketotetrose
983:Mutarotation
869:
862:
842:
835:
810:
806:
796:
786:
759:
747:
698:
682:
671:
623:
605:
598:cyclic ether
582:ether bridge
571:
491:
482:Ketopentoses
442:
295:
286:Aldopentoses
257:
237:ketopentoses
221:aldopentoses
218:
204:
171:
169:
164:
159:
152:
129:
81:biochemistry
78:
72:, and their
24:
18:
1630:Xanthan gum
1618:Amylopectin
1490:Beta-glucan
1401:Maltotriose
1216:Ketohexoses
1169:Aldohexoses
1149:Deoxyribose
1084:Erythrulose
1042:Ketotriose
1032:Aldotriose
729:Bial's test
701:chromophore
660:Deoxyribose
642:Deoxyribose
620:Deoxy sugar
568:Cyclic form
468:nucleotides
452:deoxyribose
176:deoxyribose
125:amino acids
113:nucleotides
93:deoxyribose
1406:Melezitose
1348:Isomaltose
1343:Cellobiose
1009:Aldodiose
880:0534408338
739:References
668:Properties
618:See also:
486:See also:
290:See also:
174:, such as
163:–H, where
1560:Galactose
1515:Cellulose
1505:Sizofiran
1429:Stachyose
1411:Raffinose
1378:Trehalose
1363:Lactulose
1184:Galactose
1107:Arabinose
1069:Erythrose
921:Types of
827:0365-9496
674:metabolic
594:furanoses
588:yields a
388:Arabinose
322:Arabinose
21:chemistry
1673:Pentoses
1667:Category
1652:Category
1581:Glycogen
1564:Galactan
1542:Fructose
1527:Chitosan
1500:Lentinan
1449:Acarbose
1383:Turanose
1327:Multiple
1268:Heptoses
1256:Rhamnose
1251:Fuculose
1236:Tagatose
1221:Fructose
1137:Xylulose
1132:Ribulose
1096:Pentoses
1058:Tetroses
961:Geometry
952:Pyranose
947:Furanose
717:furfural
689:pentosan
578:hydroxyl
560:Xylulose
544:Ribulose
526:Xylulose
510:Ribulose
225:aldehyde
148:hydrogen
144:carbonyl
133:hydroxyl
1623:Amylose
1571:Glucose
1546:Fructan
1536:Dextran
1532:Dextrin
1510:Zymosan
1373:Sucrose
1368:Maltose
1358:Lactose
1307:Nonoses
1302:Octoses
1295:Above 7
1231:Sorbose
1226:Psicose
1204:Mannose
1189:Glucose
1179:Altrose
1161:Hexoses
1074:Threose
1025:Trioses
930:General
770:-Ribose
752:Pentose
733:orcinol
731:, with
715:), the
705:Tollens
685:polymer
678:hexoses
235:. The
38:. The
25:pentose
1613:Starch
1608:Pectin
1603:Mannan
1598:Lignin
1575:Glucan
1552:Inulin
1520:Chitin
1246:Fucose
1209:Talose
1194:Gulose
1174:Allose
1122:Xylose
1117:Ribose
1112:Lyxose
1002:Dioses
978:Epimer
968:Anomer
942:Ketose
937:Aldose
877:
850:
825:
590:cyclic
488:ketose
444:Ribose
436:Xylose
420:Ribose
404:Lyxose
370:Xylose
354:Ribose
338:Lyxose
292:aldose
272:" or "
241:ketone
233:ribose
119:, and
85:Ribose
33:carbon
1468:(IMO)
1462:(GOS)
1456:(FOS)
1438:Other
1199:Idose
703:. In
36:atoms
27:is a
875:ISBN
848:ISBN
823:ISSN
711:for
219:The
140:bond
115:and
23:, a
815:doi
456:DNA
448:RNA
282:).
97:DNA
89:RNA
19:In
1669::
1573:/
1562:/
1544:/
1534:/
821:.
811:34
809:.
805:.
777:^
691:.
683:A
680:.
603:.
478:.
203:5-
194:10
158:4-
127:.
99:.
83:.
58:10
914:e
907:t
900:v
883:.
856:.
829:.
817::
767:D
763:"
658:-
656:L
640:-
638:D
558:-
556:L
542:-
540:L
524:-
522:D
508:-
506:D
434:-
432:L
418:-
416:L
402:-
400:L
386:-
384:L
368:-
366:D
352:-
350:D
336:-
334:D
320:-
318:D
275:L
269:D
253:2
249:2
245:3
229:4
205:y
198:O
189:H
185:5
180:C
165:x
160:x
153:x
67:5
62:O
53:H
49:5
44:C
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