Asymmetric auxiliary group
To provide a chiral reagent or a salt thereof. The chiral reagent has following chemical formula (I). In the formula (I), G 1 and G 2 are independently a hydrogen atom, a nitro group (—NO 2 ), a halogen atom, a cyano group (—CN), a group of formula (II) or (III), or both G 1 and G 2 taken together to form a group of formula (IV).
1. A compound, which is represented by formula (Va) or (Vb):
wherein:
G 1 is a hydrogen atom, a nitro group, a halogen atom, a cyano group, or a group of formula (II), (III) or (V);
G 2 is a nitro group, a halogen atom, a cyano group, or a group of formula (II), (III) or (V); or
both G 1 and G 2 are taken together to form a group of formula (IV);
wherein formula (II) is:
and
wherein G 21 to G 23 are independently a hydrogen atom, a nitro group, a halogen atom, a cyano group or C 1-3 alkyl group;
wherein formula (III) is:
and
wherein G 31 to G 33 are independently C 1-4 alkyl group, C 1-4 alkoxy group, C 6-14 aryl group, C 7-14 aralkyl group, C 1-4 alkyl C 6-14 aryl group, C 1-4 alkoxy C 6-14 aryl group, or C 6-14 aryl C 1-4 alkyl group;
wherein formula (IV) is:
and
wherein G 41 to G 46 are independently a hydrogen atom, a nitro group, a halogen atom, a cyano group or C 1-3 alkyl group;
wherein formula (V) is:
and
wherein G 51 to G 53 are independently a hydrogen atom, a nitro group, a halogen atom, a cyano group, C 1-3 alkyl group or C 1-3 alkyloxy group;
G 3 and G 4 are independently a hydrogen atom, C 1-3 alkyl group, C 6-14 aryl group, or G 3 and G 4 are taken together to form a heteroatom-containing ring that has 3 to 16 carbon atoms;
G 5 is a protective group of a hydroxyl group;
R 2 is hydrogen, halogen, alkyl-Y 1 —, alkenyl-Y 1 —, alkynyl-Y 1 —, aryl-Y 1 —, or heteroaryl-Y 1 —;
Y 1 is O;
R 3 is a group represented by —CH 2 —, —(CH 2 ) 2 —, —CH 2 NH—, or —CH 2 N(CH 3 )—; and
Bs is a group selected from the groups represented by following formula (VI) to (XI) or derivatives thereof:
2. The compound of claim 1 , wherein G 3 and G 4 are taken together to form a heteroatom-containing ring that has 3 to 16 carbon atoms.
3. The compound of claim 1 , wherein the compound is represented by formula V(a′):
4. The compound of claim 3 , wherein G 1 is a hydrogen atom.
5. The compound of claim 4 , wherein Bs is selected from:
wherein each of R 8 , R 9 and R 10 is independently C 1-10 alkyl, C 6 -C 10 aryl, C 6 -C 10 aralkyl, or C 6 -C 10 aryloxyalkyl.
6. The compound of claim 5 , wherein G 2 is a group of formula (III).
7. The compound of claim 6 , wherein R 2 is hydrogen.
8. The compound of claim 6 , wherein R 2 is —F.
9. The compound of claim 6 , wherein R 2 is alkyl-Y 1 —.
10. The compound of claim 5 , wherein G 2 is a group of formula (V).
11. The compound of claim 10 , wherein R 2 is hydrogen.
12. The compound of claim 10 , wherein R 2 is —F.
13. The compound of claim 10 , wherein R 2 is alkyl-Y 1 —.
14. The compound of claim 5 , wherein G 1 and G 2 are taken together to form a group of formula (IV).
15. The compound of claim 14 , wherein R 2 is hydrogen.
16. The compound of claim 14 , wherein R 2 is —F.
17. The compound of claim 14 , wherein R 2 is alkyl-Y 1 —.
18. The compound of claim 1 , wherein G 2 is a group of formula (II), (III) or (V), or both G 1 and G 2 are taken together to form a group of formula (IV).
19. The compound of claim 2 , wherein G 2 is a group of formula (II), (III) or (V), or both G 1 and G 2 are taken together to form a group of formula (IV).
20. A compound selected from 1a, 1b, 2a, 2b, 3a, 3b, 4a, 4b, 5a, 5b, 6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b, 10a, 10b, 11a, 11b, 12a, 12b, 13a, 13b, 14a, 14b, 15a, 15b, 16a, 16b, 17a, 17b, 18a, 18b, 19a, 19b, 20a, 20b, 21a, 21b, or 24a, wherein DMTr represents a 4,4′-dimethoxytrityl group and TOM represents a triisopropylsiloxymethyl group:
.