JP2520252B2 - Glycyrrhizin derivative - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a glycyrrhizin derivative represented by the general formula [I] having antiviral activity and a pharmaceutically acceptable salt thereof.

(In the formula, R represents SO ₃ M, and M represents H, NH ₄ , or an alkali metal atom.) [Prior Art] A large number of compounds having an antiviral effect have hitherto been reported. In particular, in recent years pathogenic virus began to spread in the world acquired immune deficiency syndrome (AIDS) (H uman I mmunodefi
ciency V irus, the search for compounds which exhibit antiviral effects against HIV) have been actively conducted. Examples of these include polyacrylic acid and dextran sulfate (De Som
er, P. et al .; J. Virol. 1968. 2 , 878; ibid. 1968, 2 , 886), suramin (De Clercq, E .; Cancer Lett. 1979, 8 , 9; Mitsuy.
a, H. et al .; Science (Washington, DC) 1984, 226 , 172) Evans Blue (Balzarini, J. et al .; Int. J. Cancer 1986, 3)
7, 451), aurin carboxylic acid (Balzarini, J et al;. Bioche
m.Biophys.Res.Commun. 1986, 136 , 64) 3'-azide-
2 ', 3'-dideoxythymidine (AZT) (Mitsuya, H. et al .;
Proc.Natl.Acad.Sci.USA1985, 82 , 7096), 2 ', 3'
-Dideoxynucleoside (Mitsuya, H. et al; Proc. Natl. A
cad.Sci.USA1986, 83 , 1911), Glycyrrhizin (Masahiko Ito et al .; The 34th Annual Meeting of the Japanese Society for Virology 1986, p.
70) etc. have been reported.

[Problems to be solved by the invention]

AZT is known as the most effective compound for not only in vitro but also clinically against viruses, especially HIV. Although it has a long life-prolonging effect on AIDS patients, it can be a therapeutic or preventive drug. Since it does not exist and there are problems with side effects, it has been desired to develop other compounds effective for treatment and prevention as soon as possible.

In addition, since these drugs generally need to be continuously administered for a long period of time, it has been strongly desired that toxicity and side effects be as low as possible.

[Means for solving problems]

The present invention has been made to solve such a problem, and was made by discovering that glycyrrhizin pentasulfate having the general formula [I] has the intended effect.

In order to produce the compound represented by the general formula [I] of the present invention, glycyrrhizin may be sulfated by a conventional method, and one example thereof is shown by a reaction formula as follows.

That is, an excess amount of chlorosulfonic acid is added to glycyrrhizin in pyridine at a low temperature to cause a sulfation reaction. Sulfates Li oxide as sulfates agent - pyridine _{(SO 3 · C 5 H 5} N:.. Baumgalten, P; Ber 59
1160 (1926)) may be used. In order to isolate the compound of the general formula [I] from the reaction solution, commonly used means,
For example, methods such as liquid-liquid extraction, ion exchange chromatography, thin layer chromatography, and recrystallization may be used alone or in combination.

The compound of the general formula [I] of the present invention can be changed to a pharmacologically acceptable salt, if necessary. As salt,
Examples thereof include alkali metal salts such as potassium and sodium, ammonium salts, and these salts can be easily produced by a conventional method.

The compound of the general formula [I] of the present invention has not only a strong antiviral effect against viruses, particularly retroviruses, but also a wide effective concentration range, low toxicity, and a reverse transcriptase activity inhibitory effect. It is useful as a therapeutic and preventive agent for AIDS.

〔Example〕

Example 1 (Glycyrrhizin pentasulfate / ammonium salt) 8.2 g of glycyrrhizin was dissolved in 100 ml of pyridine, and the solution was dissolved at 0 ° C.
Then, 5.3 ml of chlorosulfonic acid was added dropwise. After stirring overnight at room temperature, pyridine was distilled off, and the oily residue was purified by silica gel chromatography (chloroform: methanol 5: 1). Aqueous ammonia was added to the fraction containing the target product [I] to adjust the pH. The precipitated crystals were collected by filtration and washed with ethyl acetate to give 5.0 g of crystals.

Melting point: 175 ° C (decomposition) Rf: 0.42 (n-butanol: acetic acid: water 2: 1: 1) ▲ [α] ²¹ _D ▼: 42.6 (c = 1, water) Elemental analysis value (C ₄₂ H ₈₆ N ₈ O ₃₁ S ₅ ) Actual value: C37.50 H6.78 N7.97 S11.60 Calculated value: C37.11 H6.37 N8.24 S11.78 [Crop] Suppressive effect against cell damage caused by HIV infection MT4 cells After the cells were infected with HIV, the compound of Example 1 (GLS) was added to the cells at a predetermined concentration, and the cells were cultured for 6 days. By observing the number of surviving cells after 6 days, it was determined how much the cell damage due to HIV infection was suppressed.
Glycyrrhizin (GL) was used as a control drug. The results are shown in FIG. □ indicates MT-4 cells. Also,
■ indicates the effect on cells infected with HIV.

The control GL was 1.25 mg / ml, and the cytotoxic effect of HIV was recognized, while GLS was 0.25 to 2.5 mg / ml (1/5 to 2 of GL).
The inhibitory effect was shown in a wide concentration range. GLS has an inhibitory effect even at low concentrations, and since it has low toxicity to cells,
It can be seen that the effective concentration range is wide.

This experiment was carried out by Harada, S. et al .; Science, 1985, 229 , 563.
It was performed according to the method described in -566. The following experiments are similar.

Inhibition effect of HIV antigen positive on HIV-infected cells MT-4 cells
Infected with HIV and given concentration of GLS or GL as control
After incubating for a certain period of time, the indirect fluorescent antibody method (IF
The cells that became HIV antigen positive by the method) were measured. The results are shown in FIG.

● means GLS or no GL added ○ means 〃 〃 0.125 mg / ml ■ means 〃 〃 0.25 〃 □ means 〃 〃 0.5 〃 ▲ means 〃 〃 1 〃 △ means 〃 〃 2 〃.

With no drug added, the antigen positive rate was 82% on the 3rd day of culture and 100% on the 6th day, but when GLS was added at 0.25 to 0.5 mg / ml, the appearance of antigen-positive cells was 3% or less, which was significant. You can see that it was suppressed to. In the case of GL, the inhibitory effect does not appear unless 1 to 2 mg / ml is added.

HIV and tri myelogenous leukemia virus (A vian M ye
loblastosis V irus; an inhibitory effect on AMV) reverse transcriptase activity are shown in Figure 3.

○ is for HIV and ● is for AMV reverse transcriptase activity.
The inhibitory effect of GLS is shown.

While GL had no reverse transcriptase inhibitory effect, GLS had an inhibitory effect.

〔The invention's effect〕

The compound of the general formula [I] of the present invention exerts an inhibitory effect on cell damage due to virus infection, an inhibitory effect on virus antigen positivity of infected cells, an inhibitory effect on reverse transcriptase of retrovirus, etc., and also has low toxicity, It can be useful as an antiviral agent and a drug useful for treating and preventing viral diseases.

[Brief description of drawings]

Figure 1 shows the inhibitory effect of GLS or GL on cell damage caused by HIV infection. Figure 2 shows H of HIV-infected cells.
FIG. 3 shows the inhibitory effect of GLS or GL on IV antigen positivity, and FIG. 3 shows the inhibitory effect of GLS on the reverse transcriptase activity of HIV and AMV.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Yoshiharu Nakajima 4-6-7 Shimochiai, Shinjuku-ku, Tokyo Inside Fuji Revio Co., Ltd. (72) Inventor Naoki Yamamoto 1-7-12 Higashikobayama-cho, Ube City, Yamaguchi Prefecture ( 56) References JP-A-63-33332 (JP, A)

Claims (1)

(57) [Claims] 1. A general formula (I) A glycyrrhizin derivative represented by and a salt thereof (in the formula,
R represents —SO ₃ M, and M represents H, NH ₄ , or an alkali metal atom. ).