JPH10279580A - Reducing reagent - Google Patents

Abstract

(57) [Summary] (With correction) [Solution] The following formula (I): (Wherein, R ¹ represents a C _1-4 alkyl group, R ² represents a C _1-6 alkyl group, and n represents an integer of 8 to 13). The above compound can be used as a reducing reagent in the presence of magnesium ions and the like, and has a characteristic that the reaction proceeds stereospecifically.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a compound useful as a reducing reagent.

[0002]

BACKGROUND ART Coenzyme NAD involved in redox reaction in vivo
Various model compounds have been synthesized as analogs of H 2, and stereoselective asymmetric reduction reactions for active ketones have been actively reported in recent years. In these biological model reactions, the selectivity of the dihydropyridine ring for prochiral hydrogen is an important factor for asymmetric expression (De Kok, P.
M., et al., J. Org.Chem., 54, p.1313, 1989; Combr
et, Y., et al., Tetrahedron, 49, p.5237, 1993). However, these previously proposed NADH models are Mg
There were problems with ²⁺ chelation and face selectivity of dihydropyridine, which was not always satisfactory from the viewpoint of the asymmetric yield of the reaction.

[0003]

DISCLOSURE OF THE INVENTION The present inventors have developed a crosslinked nicotine having a specific parapyridinophane structure for the purpose of efficiently performing this face-selective reduction reaction. An acid amide derivative was selected, and the possibility of using it as a NADH model was studied diligently. As a result, when a compound in which a dihydropyridine skeleton, which is a coenzyme function site, is bonded to an oligomethylene cross-linked chain seen on the enzyme wall surface, the substrate can selectively react from a surface with little steric hindrance, It was found that stereoselective and stereospecific asymmetric reduction reactions proceeded at various temperatures. The present invention has been completed based on these findings.

That is, the present invention provides the following formula (I):

Embedded image (Wherein, R ¹ represents a C _1-4 alkyl group, R ² represents a C _1-6 alkyl group, and n represents an integer of 8 to 13).

According to another aspect of the present invention, there is provided the following formula (II):

Embedded image (Wherein, R ¹¹ represents a C _1-4 alkyl group, R ¹² represents a C _1-6 alkyl group, and m represents an integer of 8 to 13).

According to still another aspect of the present invention, there is provided a reducing reagent containing the compound represented by the above formula (I), preferably an asymmetric reducing reagent.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the above general formula (I), R ¹ is C
_1-4 represents an alkyl group having 1 to 4 carbon atoms. As the C _1-4 alkyl group, any of a straight chain or a branched chain may be used, and for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-propyl group and the like can be used.
Of these, a methyl group is preferably used. R ² is C
_{Represents a 1-6} alkyl group, the C _1-6 alkyl group may be any of a straight chain or a branched chain, for example, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl Group, sec-butyl group, tert-butyl group and the like. Among them, isopropyl, isobutyl, tert-butyl and the like are preferable, and isopropyl is particularly preferable. n represents an integer of 8 to 13, and is preferably 10.

In the general formula (II), R ¹¹ represents a C _1-4 (C _1-4 ) alkyl group. As the C _1-4 alkyl group, any of a straight chain or a branched chain may be used, and for example, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-propyl group and the like can be used. Of these, a methyl group is preferably used. R ¹² represents a C _1-6 alkyl group, and the C _1-6 alkyl group may be any of a straight chain or a branched chain, for example, ethyl group, n-propyl group, isopropyl group, n- Butyl group, isobutyl group,
A sec-butyl group, a tert-butyl group and the like can be used. Of these, isopropyl, isobutyl, te
An rt-butyl group is preferred, and an isopropyl group is particularly preferred. m represents an integer of 8 to 13, preferably 10.

The compound of the present invention represented by the formula (I) may form an acid addition salt. Examples of such a salt include mineral acids such as hydrochloride, sulfate, and nitrate, and organic acid salts such as methanesulfonate, paratoluenesulfonate, tartrate, and oxalate. However, the present invention is not limited to these. Further, the compound represented by the formula (II) of the present invention forms a quaternary salt, and as a counter ion, iodine ion, bromine ion, chloride ion and the like can be used.

The compound represented by the formula (I) of the present invention can be easily produced by the method described in the following scheme. The compound in the scheme is a compound in which R ¹ is a methyl group, R ² is an isopropyl group, and n is 10 in the above formula (I), and is a preferred compound of the present invention. It is not limited to. In addition, specific examples of other manufacturing methods are described in the examples of the present specification, and therefore, if necessary, based on the general description of these schemes and the specific description of the examples, Those skilled in the art will readily understand that by appropriately selecting reaction reagents and reaction conditions, the compounds included in the general formula (I) can be easily produced. Each of the compounds represented by the formula (I) of the present invention can exist as optical isomers without being based on asymmetric carbon. The conceptual diagram of each molecular structure is described in the following scheme, but any optically active substance is included in the scope of the present invention.

[0011]

Embedded image

After reacting 2 which is a Vilsmeier reaction product of cyclododecanone 1 with NaN ₃ , light irradiation is performed using a Pyrex glass container to obtain an azirine derivative 3. After converting this compound 3 to iminophosphorane 4 with triphenylphosphine, it is reacted with methyl propiolate in toluene at 140 ° C. to convert nicotinic acid ester 5 having a parapyridinophan structure and its isomer 6 into 21 respectively. % And 8% yield. In the ¹ H-NMR of compound 5, the presence of compound 5 can be easily confirmed since the semi-protons of the methylene bridge chain appear unequally and the methylene proton shielded by the pyridine ring appears at 0.13 ppm. it can. After hydrolysis of compound 5, it can be amidated with (S) -valinol and the resulting diastereomeric mixture separated to give 7a and 7b. Since the compound 7a gave a plate-like single crystal, its structure was determined by X-ray crystal diffraction. Compounds 7a and 7b can be converted to pyridinium salts, respectively, and reduced with sodium dithionite to give compounds 8a and 8b.

The compound represented by the formula (I) of the present invention has a property of transferring a hydrogen anion to a substrate molecule (reduced molecule) and oxidizing itself to be converted into a compound of the formula (II). . This reaction suitably proceeds in the presence of a metal ion such as a magnesium ion, and when an optically active compound of the formula (I) is used, the reaction proceeds stereospecifically, resulting in an extremely high asymmetric yield. give. For example, according to the following scheme, methylbenzoyl formate and each optical isomer of a compound of the formula (I) (a compound in which R ¹ is a methyl group, R ² is an isopropyl group, and n is 10) are dissolved in acetonitrile at room temperature with magnesium. 5 in the presence of ions (magnesium perchlorate)
After reacting for days, the reduced forms (R) -methyl mandelate and (S) -methyl mandelate are 99% ee and
The compound of the formula (II) (R ¹¹ is a methyl group, R ¹² is an isopropyl group, and m
Is a compound of formula (10). Since the compound of the formula (II) obtained by the above reaction does not contain each diastereomer, it has a feature that an optically pure compound of the formula (I) can be easily regenerated. .

[0014]

Embedded image

[0015]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to Examples, but the scope of the present invention is not limited to the following Examples.

Example 1: Hydrolysis of crosslinked nicotinic acid ester 5

Embedded image

Compound 5 (1.65 g, 6.00 mmol) and LiOH
_{· H 20 (1.26 g, 30.0} mmol) in methanol - was dissolved in water (9/1) and stirred overnight at room temperature. After completion of the reaction, the solvent was distilled off under reduced pressure, water was added, and the mixture was extracted twice with ether. After adjusting the pH of the water bath to 5 with hydrochloric acid, the mixture was extracted three times with tetrahydrofuran-ethyl acetate (1/1). Dry the organic layer (MgSO ₄ )
After filtration, the filtrate was concentrated under reduced pressure to obtain crude crystals of carboxylic acid 6. Ether was added to the crude crystals and filtered,
The solid was washed with ether and crosslinked nicotinic acid (1.264 g, 81
%).

Example 2: Synthesis of bridged nicotinamide 14a, b

Embedded image

The crosslinked nicotinic acid (65.4 mg, 0.25 mmol) was added to SO
It was dissolved in Cl ₂ (0.3 ml) and distilled under heating for 2 hours. After completion of the reaction, excess SOCl ₂ was distilled off under reduced pressure to obtain crosslinked nicotinic anhydride. After dissolving this acid anhydride in chloroform (1 ml), a chloroform solution (1 ml) of L-valinol (38.7 mg, 0.375 mmol) and triethylamine (37.9 mg, 0.375 mmol) was added at 0 ° C., and the mixture was added at room temperature. Stir for 2 hours. After completion of the reaction, chloroform and water were added, and after removing the water tank, the organic layer was washed with water and brine. Dry the obtained organic layer
(MgSO ₄ ) and filtration, the filtrate was concentrated under reduced pressure to give a crude crosslinked nicotinamide. The crude product was purified on silica gel thin-layer chromatography using ethyl acetate-hexane (3/2) to give 14a (41.1 mg, 48%) and 14a.
b (41.1 mg, 48%) was obtained.

14a: colorless plate; IR (CHCl ₃ ): 363
0, 3430, 2935, 1655 cm ^-1 ; ¹ H NMR (500 MHz, CDC
l ₃ ): δ = 0.36 (1H, m), 0.52-0.63 (2H, m), 0.72-0.
85 (5H, m), 1.04 (3H, d, J = 6.8 Hz), 1.05 (3H, d,
J = 6.8 Hz), 1.12 (2H, m), 1.21 (2H, m), 1.45 (1H,
m), 1.65 (1H, m), 1.80 (2H, m), 2.02 (1H, oct, J
= 6.8 Hz), 2.61 (1H, ddd, J = 13.7, 10.0, 4.3 Hz),
2.73 (1H, ddd, J = 13.7,6.3, 4.4 Hz), 2.85 (1H, d
dd, J = 13.0, 9.0, 4.3 Hz), 3.26 (1H, ddd, J = 13.
0, 8.0, 4.4 Hz), 3.78 (1H, dd, J = 11.1, 5.8 Hz),
3.82 (1H, dd, J = 11.1, 3.4 Hz), 3.96 (1H, dddd, J
= 8.1, 6.8, 5.8, 3.4, Hz), 6.01 (1H, broad d, J =
8.1 Hz), 7.56 (1H, d, J = 2.1 Hz), 8.41 (1H, d, J
= 2.1 Hz); ¹³ C NMR (125 MHz, CDCl ₃ ): δ = 19.0, 19.
7, 24.7, 25.2, 26.4, 26.5, 27.7,27.8, 27.9, 28.3,
29.2, 31.9, 35.1, 57.6, 63.8, 132.2, 134.7, 135.8,
150.4, 157.7, 169.5; [α] _D ²⁶ = +64.9 (c = 1, CH
Cl ₃ ); MS (EI): m / z (%): 346 (31) [M ⁺ ], 244 (100);
HR-MS (FAB): m / z 347.2696 [M ⁺ H ⁺ ; calcd forC ₂₁ H
₃₅ O ₂ N ₂ : 347.2699].

14b: oil; IR (CHCl ₃ ): 3630, 3430, 293
5, 1656 cm ^-1 ; ¹ H NMR (500 MHz, CDCl ₃ ): δ = 0.35
(1H, m), 0.53 (1H, m), 0.60 (1H, m), 0.71-0.85 (5
H, m), 1.01 (3H, d, J = 6.8 Hz), 1.04 (3H, d, J =
6.8 Hz), 1.06-1.26 (4H, m), 1.44 (1H, m), 1.64 (1
H, m), 1.79 (2H, m), 2.00 (1H, oct, J = 6.8 Hz),
2.60 (1H, ddd, J = 13.3, 10.3, 6.3 Hz), 2.71 (1H, d
dd, J = 13.3, 5.6, 5.1 Hz), 2.83 (1H, ddd, J = 13.
3, 9.0, 3.9 Hz), 3.27 (1H, ddd, J = 13.3, 7.5, 4.1
Hz), 3.80 (1H, dd, J = 11.3, 5.6 Hz), 3.85 (1H, d
d, J = 11.3, 3.4 Hz), 3.97 (1H, dddd, J = 8.6, 6.
8, 5.6, 3.4 Hz), 6.12 (1H, broad d, J = 8.6 Hz),
7.53 (1H, d, J = 2.1 H), 8.39 (1H, d, J = 2.1 H)
z); ¹³ C NMR (125 MHz, CDCl ₃ ): δ = 18.9, 19.6, 24.
6, 25.2, 26.4, 26.5, 27.7, 27.8, 27.9, 28.3, 29.1,
31.9, 34.9, 57.4, 63.6, 132.2, 134.7, 135.8, 150.
2, 157.3, 169.3; [α] _D ²⁶ = -80.1 (c = 1, CHC
l ₃ ); MS (EI): m / z (%): 346 (35) [M ⁺ ], 244 (100); H
R-MS (FAB): m / z 347.2724 [M ⁺ H ⁺ ; calcd for C ₂₁ H
₃₅ O ₂ N ₂ : 347.2699].

EXAMPLE 3 Synthesis of Bridged Pyridinium Salt 15ax

Embedded image

Crosslinked nicotinamide 14a (34.6 mg, 0.1 m
mol) with a mixture of methyl iodide and acetonitrile (1/1, 0.
5 ml) and stirred at 50 ° C. for 24 hours. After completion of the reaction, excess methyl iodide and acetonitrile were distilled off under reduced pressure,
The crosslinked pyridinium salt 15ax (48.8 mg, 100%) was obtained. 15ax: yellow solid; IR (CHCl ₃ ): 3690, 3400, 3223,
2941, 1669 cm ^-1 ; ¹ H NMR (500 MHz, CDCl ₃ ): δ =-
0.03 (1H, m), 0.68-0.95 (7H, m), 1.05 (3H, d, J =
6.8 Hz), 1.07 (3H, d, J = 6.8 Hz), 1.09-1.28 (4H,
m), 1.55 (1H, m), 1.73 (1H, m), 1.79 (1H, m), 2.01,
(1H, m), 2.10 (1H, oct, J = 6.8 Hz), 2.82 (1H, dd
d, J = 14.0, 9.2, 4.9 Hz), 2.96 (1H, ddd, J = 14.
0, 7.0, 5.2Hz), 3.43 (1H, ddd, J = 15.3, 5.2, 4.9
Hz), 3.58 (1H, ddd, J = 15.3, 10.4, 5.2 Hz), 3.77
(1H, dd, J = 11.9, 3.7 Hz), 3.81 (1H, dd, J = 11.
9, 6.4 Hz), 3.93 (1H, dddd, J = 7.9, 6.8, 6.4, 3.7
Hz), 4.42 (3H, s), 8.31 (1H, s), 8.34 (1H, d, J =
7.9 Hz), 8.46 (1H, s); ¹³ C NMR (68 MHz, CDCl ₃ ): δ
= 19.7, 19.8, 24.1, 25.0, 25.9 (2C), 26.0, 26.87,
26.90, 27.8, 29.3,31.2, 32.0, 47.1, 58.9, 62.7, 1
39.5, 140.8, 145.2, 145.5, 155.6, 164.8; [α] _D ²³
= +61.8 (c = 1, CHCl ₃ ); MS (ESI): m / z (%): 361 (1
^{00) [M - I -]} ; MS (ESI, negative): m / z (%) 615 (10
^{0) [M + I -]} , 127 (35) [I -].

The N-methylation reaction of the crosslinked nicotinamide 14b was carried out in the same manner to obtain a crosslinked pyridinium salt 15bx.

Embedded image

15bx: yellow solid; IR (CHCl ₃ ): 3411,
3232, 2941, 1671 cm ^-1 ; ¹ H NMR (500 MHz, CDCl ₃ ):
δ = -0.12 (1H, m), 0.70-0.99 (7H, m), 1.01 (3H,
d, J = 6.8 Hz), 1.02 (3H, d, J = 6.8 Hz), 1.12-1.2
8 (4H, m), 1.55 (1H, m), 1.73 (1H, m), 1.79 (1H,
m), 1.98, (1H, oct, J = 6.8 Hz), 2.04 (1H, m), 2.8
3 (1H, ddd, J = 14.3, 8.8, 5.2 Hz), 2.94 (1H, ddd,
J = 14.3, 7.3, 5.4 Hz), 3.00 (1H, dd, J = 7.6, 6.7
Hz) 3.46 (1H, dt, J = 15.3, 5.2 Hz), 3.58 (1H, dd
d, J = 15.3, 10.3, 5.4 Hz), 3.80 (1H, ddd, J = 11.
9, 6.7, 3.7 Hz), 3.86 (1H, dt, J = 11.9, 7.6 Hz),
4.01 (1H, ddd, J = 7.6, 6.8, 3.7 Hz), 4.42 (3H,
s), 8.07-8.11 (1H, broad s), 8.09 (1H, d, J = 1.5
Hz), 8.40 (1H, d, J = 1.5 Hz); ¹³ C NMR (68 MHz, CDC
l ₃ ): δ = 19.4, 19.5, 24.1, 24.9, 25.88, 25.93, 2
6.1, 26.8, 26.9, 28.0, 29.4, 31.3, 32.5, 47.2, 58.
6, 62.3,139.9, 140.7, 143.5, 145.0, 156.6, 164.8;
[α] _D ²⁶ = -75.4 (c = 1, CHCl ₃ ); MS (ESI): m / z
(%): 361 (100) [M - I -]; MS (ESI, negative): m / z
(%) 615 (100) [ M + I -], 127 (35) [I -].

Example 4: Synthesis of compound 16a and asymmetric reduction reaction

Embedded image

Crosslinked pyridinium salt 15ax (19.5 mg, 0.040
was dissolved in methylene chloride (0.8 ml), a 0.5 N aqueous solution of sodium dithionite (140 mg, 0.895 mmol) in sodium carbonate (1.6 ml) was added, and the mixture was stirred at room temperature in a dark place for 14 hours.
After completion of the reaction, the mixture is extracted three times with dichloromethane and dried (MgSO ₄ )
After filtration, the filtrate was concentrated under reduced pressure to obtain compound 16a. 16a: oil; ¹ H NMR (500 MHz, CDCl ₃ ): δ = 0.85-1.65
(16H, m), 0.95 (3H, d, J = 6.8 Hz), 0.98 (3H, d, J
= 6.8 Hz), 1.95 (1H, oct, J = 6.8 Hz), 2.05 (1H, dd
d, J = 13.7, 12.4, 4.7 Hz), 2.15 (1H, dtd, J = 13.
7, 3.2, 1.7 Hz), 2.25 (1H, dtd, J = 14.5, 4.3, 1.8
Hz), 2.79 (1H, broad d, J = 16.3 Hz), 2.90 (1H, d
d, J = 16.3, 0.9 Hz), 3.07 (3H, s), 3.45 (1H, ddd,
J = 14.5, 11.5, 4.1 Hz), 3.52 (1H, m), 3.59 (1H,
m), 3.66-3.72 (2H, m), 5.60 (1H, broad d, J = 6.0
Hz), 5.73 (1H, d, J = 0.9 Hz); ¹³ C NMR (125 MHz, C
DCl ₃ ): δ = 18.5, 19.7, 23.6, 25.1, 25.5, 25.7, 2
6.7, 27.03, 27.04, 27.2,27.82, 27.83, 29.3, 30.7,
36.7, 58.1, 65.6, 101.3, 109.6, 130.6, 147.7,172.
8.

[0028]

Embedded image

This 16a was immediately converted to anhydrous acetonitrile (0.1
8 ml), and methyl benzoylformate (5.93 mg, 0.03
54 mmol) and magnesium perchlorate (8.9 mg, 0.040 m
mol) was added and the mixture was stirred at room temperature in the dark for 5 days. After completion of the reaction, water was added to the reaction solution, and the mixture was extracted with chloroform. The organic layer was dried (MgSO ₄ ), filtered, and the filtrate was concentrated under reduced pressure.
The obtained mixture was purified by silica gel column chromatography, and ether-hexane (1/1) solvent was used.
Obtain (R) -methyl mandelate (64%, 99% ee) and pyridinium perchlorate 15ay (66%) in ethanol solvent
I got Similarly, the reaction was carried out at 50 ° C (24 hours) and 75 ° C (6 hours), and (R) -ethyl mandelate was 70% (99%
ee) and 63% (98% ee) in yields (81% and 65% for 15ay).

15ay: ¹ H NMR (500 MHz, CDCl ₃ ): δ =-
0.14 (1H, m), 0.68-0.98 (6H, m), 1.02 (6H, d, J =
6.8 Hz), 1.14 (1H, m), 1.23 (3H, m), 1.62 (1H, m),
1.70 (1H, m), 1.77 (1H, m), 1.97 (1H, oct, J = 6.
8 Hz), 1.99, (1H, m), 2.83 (1H, ddd, J = 14.0, 9.
0, 5.1 Hz), 2.92 (1H, ddd, J = 14.1, 6.8, 5.3 Hz),
3.33 (1H, ddd, J = 15.4, 5.6, 5.1 Hz), 3.40 (1H,
ddd, J = 15.4, 9.8, 5.1Hz), 3.68 (1H, dd, J = 11.
9, 6.8 Hz), 3.77 (1H, dd, J = 11.9, 3.2 Hz), 3.93
(1H, dtd, J = 8.5, 6.8, 3.2 Hz), 4.35 (3H, s), 7.3
6 (1H, d, J = 8.5Hz), 8.26 (1H, d J = 1.6 Hz), 8.5
1 (1H, d J = 1.6 Hz); ¹³ C NMR (125 MHz, CDCl ₃ ): δ
= 19.1, 19.6, 24.0, 24.9, 25.86, 25.94, 26.1, 26.
8, 26.9, 27.8, 29.2, 30.5, 31.1, 46.2, 58.6, 63.0,
139.3, 141.1, 144.9, 146.0, 154.7, 165.2; MS (ES
I): m / z (% ): 361 (100) [M - ClO 4 -]; MS (ESI, nega
tive): m / z (% ) 559 (62) [M + ClO 4 -], 99 (100) [ClO
₄ ^-].

Compound 16b was synthesized in the same manner and similarly subjected to an asymmetric reduction reaction to obtain methyl (S) -mandelate and pyridinium perchlorate 15by. Room temperature (4 days) and
The yields of (R) -ethyl mandelate at 75 ° C (6 hours) were 64% (97% ee) and 63% (98% ee), respectively (15
by is 60% and 71% respectively). From these results, it was clarified that this reduction reaction proceeded stereospecifically. The enantioselectivities of these reactions are compound 16a and
It is governed solely by the absolute structure of pyridinophane at 16b and does not depend on the steric nature of the amide side chain derived from (S) -Valinol. This means that the compound (I) of the present invention
Shows that the oligomethylene bridged chain almost completely shields one surface of the dihydropyridine ring, and it can be understood that the substrate reacts face-selectively via magnesium ions to exhibit high stereoselectivity. Further, the recovered pyridinium salts 15a and 15b do not contain each diastereomer, and the compound (I) of the present invention can be reused.
Shows usefulness as NADH model compound

[0032]

Embedded image

16b: oil; ¹ H NMR (500 MHz, CDCl ₃ ): δ
= 0.84-1.65 (16H, m), 0.95 (3H, d, J = 6.8 Hz), 0.9
7 (3H, d, J = 6.8 Hz), 1.89 (1H, oct, J = 6.8 Hz),
2.05 (1H, ddd, J = 13.2, 12.4, 4.7 Hz), 2.15 (1H,
broad d, J = 12.4 Hz), 2.21 (1H, dtd, J = 14.5, 4.
3, 1.7 Hz), 2.80 (1H, d, J = 16.0 Hz), 2.90 (1H, d,
J = 16.0 Hz), 3.08 (3H, s), 3.44 (1H, broad s),
3.57 (1H, dd, J = 10.7, 7.3 Hz), 3.62 (1H, m), 3.
70 (1H, dd, J = 10.7, 3.4 Hz), 3.79 (1H, m), 5.55
(1H, broad s), 5.73 (1H, s); ¹³ C NMR (125 MHz, CDC
l ₃ ): δ = 18.5, 19.7, 23.5, 24.9, 25.4, 25.8, 26.
4, 26.7, 27.0, 27.2, 27.4, 27.9, 29.6, 30.8, 36.7,
57.6, 65.5, 100.3, 109.9, 130.5, 149.4, 171.6.

15by: ¹ H NMR (500 MHz, CDCl ₃ ): δ =-
0.16 (1H, m), 0.68-1.02 (7H, m), 0.99 (3H, d, J =
6.8 Hz), 1.00 (3H, d, J = 6.8 Hz), 1.02 (3H, d, J
= 6.8 Hz), 1.12-1.32 (4H, m), 1.57-1.82 (4H, m),
1.91, (1H, oct, J = 6.8 Hz), 2.04 (1H, m), 2.84 (1
H, ddd, J = 14.3, 8.5, 5.2 Hz), 2.92 (1H, ddd, J =
14.3, 6.7, 5.2 Hz), 3.35 (1H, dt, J = 15.3, 5.1 H
z) 3.53 (1H, ddd, J = 15.3, 10.4, 5.5 Hz), 3.72 (1
H, dd, J = 11.9, 8.2 Hz), 3.82 (1H, dd, J = 11.9,
3.6 Hz), 4.01 (1H, dddd, J = 8.2, 7.9, 6.8, 3.6 H
z), 4.37 (3H, s), 7.29 (1H, d, J = 7.9 Hz), 8.09
(1H, d, J = 1.5 Hz), 8.41 (1H, d, J = 1.5 Hz); ¹³ C
NMR (68 MHz, CDCl ₃ ): δ = 18.9, 19.5, 24.1, 24.8,
25.9, 26.0, 26.2, 26.8, 26.9, 27.9, 29.3, 30.4, 3
1.2, 46.3, 58.3, 63.1, 139.6, 140.9, 143.6, 145.7,
155.9, 165.1; MS (ESI): m / z (%): 361 (100) (M ^- ClO
^{_{4 -]; MS (ESI,}} negative): m / z (%) 559 (38) [M + ClO
^{_{4 -], 99 (100)}} [ClO 4 -].

[0035]

The reduction reaction using the compound of the present invention proceeds stereospecifically and gives an extremely high optical yield. Therefore, the compound of the present invention is useful as a reducing reagent, preferably an asymmetric reducing reagent.

Claims (4)

[Claims] (1) The following formula (I): (Wherein, R ¹ represents a C _1-4 alkyl group, R ² represents a C _1-6 alkyl group, and n represents an integer of 8 to 13). 2. The following formula (II): (Wherein, R ¹¹ represents a C _1-4 alkyl group, R ¹² represents a C _1-6 alkyl group, and m represents an integer of 8 to 13). 3. A reducing reagent comprising the compound according to claim 1. 4. The reagent according to claim 3, which is an asymmetric reducing reagent.