JPS597698B2 - Fueganomycin group antibiotics - Google Patents

Description

Detailed Description of the Invention The present invention is based on the general formula (I) (wherein R1 is a hydrogen atom or a hydroxyl group, R2 is a hydroxyl group, an aspartic acid residue, an aspartyl-arginine residue, or an aspartyl-glycyl-prolyl-threonine residue). Indicates the group.

) is related to the feganomycin group antibiotics. The present inventors have found that in the above general formula (1), R
A compound in which 1 and R2 are both hydroxyl groups is Feganomycin (hereinafter referred to as "PHG"), a compound in which R1 is a hydroxyl group and R2 is an asbaragic acid residue is Feganomycin D (hereinafter referred to as "PHGD"), and R1 is a hydroxyl group. , a compound in which R2 is an aspartyl arginine residue is referred to as feganomycin DR (hereinafter referred to as "PHG-D").
R]. ), R1 is a hydroxyl group, R2 is an aspartyl group,
A compound represented by glycyl, prolyl, and threonine residues is referred to as ``PHG-DGPT'' (hereinafter referred to as [PHG-DG
PT”. ), a compound in which R1 is a hydrogen atom and R2 is an aspartic acid residue was named deoxyfueganomycin D (hereinafter referred to as "deoxyPHG-D"). All of these are new antibiotics. Note that the present invention Hereinafter, these compounds will be referred to as feganomycin group antibiotics.Next, the physical and chemical properties of the feganomycin group antibiotics of the present invention will be shown.1.Appearance: colorless powder2.Elemental analysis value (%):3.Molecular weight:4 .Melting point: The fueganomycin group antibiotics do not show a clear melting point or decomposition point, but PHG-D, PHG-DRldeoxyPHG-D has a temperature of 230°C or higher, and PHG, .P
HG-DGPT gradually decomposes from 210°C.

5. Specific rotation: 6. FIG. 1 shows the ultraviolet absorption spectrum of ultraviolet absorbing Svectorifeganomycin group antibiotics.

PHG,. PHG-D,. PHG-DRlPHG-DG
PT has a shoulder at 282 nm and an absorption maximum at 282 nm. Their 1% E is 27.2 and 22.417.61crr respectively
L--))0)
It is 16.2.

1 Also, deoxyPHG-D is 277nm 1% 1% (El4.5) and 283nm (El4.3) 1CTrL
It has two absorption maxima at ゜1CTI1゛.

7. Infrared absorption spectrum: PHG measured as potassium bromide tablets. PHG-D,. PHG-DR,. Poor PH
The infrared absorption spectra of G-DGPT and deoxyPHG-D are shown in FIGS. 2 to 6.

The absorption maximum value (wave number CrrL-1) of each compound is shown below. PHG; 3350, 3027 (Sh), 2970
、． C16601161011535, 1475, 14
45, 1405, 1375, 1335, 1285, 12
35, 1190110701990, 940, 925,
855, 820.

PHG-D; 340013230 (Sh), J
3O8O(Sh), 2970116601161011
535, 1475, 1445, 1400, 133011
30011235, 1190, 10701990, 94
0, 925, 855, 8200- PHG-DR: 3350, 3170 (Sh), 3070
(Sh), 2930, 165011530, 1465,
1435, 1400, 1330, 1285, 1235,
1170, 1070, 9901940, 930, 855
, PHG-DGPT; 3430, 3050 (Sh), 2
970, 1650, 155011530, 144011
395, 1330, 1235, 119011075, 9
95, 925, 855, 8200 DeoxyPHG-D; 3430, 3230 (Sh), 3
070 (Sh), 295011660, 1530, 14
3011400113301130011230, 11
80, 1090, 990, 930, 850, 8150 3. Solubility in solvents: Feganomycin group antibiotics are soluble in methanol, ethanol, propanol, acetone,
Barely soluble in organic solvents such as ethyl acetate, butyl acetate, ether and benzene.

Also PHG,. PHG-DRlPHG-DGPT is highly soluble in water, but PHG-D and deoxyPHG-D have lower solubility than these. →．． Color reaction: Feganomycin group antibiotics show positive results in ninhydrin reaction, Lydon-Smith reaction, pentacyanoaqueofriate reaction, and Pauli reaction, and negative results in tetrazolium chloride reaction and Ehrlitsug reaction.

In the Sakaguchi reaction, only PHGDR is positive and the others are false positive. 1
0. Acid hydrolysis product: A feganomycin group antibiotic was hydrolyzed in a sealed tube at 105° C. for 17 hours with 6N hydrochloric acid, and then amino acid analysis was performed to determine the molar ratio.

The results are shown in Table 2. Based on the above, it was determined that the feganomycin group antibiotic of the present invention is a new compound.

*Next, Tables 3 and 4 show the antibacterial spectra of the feganomycin group antibiotics of the present invention. As shown in Tables 3 and 4, the feganomycin group antibiotics show almost no activity against Gram-positive bacteria, Gram-negative bacteria, molds, and yeasts. However, it showed antibacterial activity against acid-fast bacteria, and among them, PHG-DR was most strongly inhibited.
Further, it did not show cross-resistance to known antibiotic-resistant Mycobacterium 607. The toxicity (LD5O) of feganomycin DR to mauns is 400η/K9 (1.
v. ) The above shows that the toxicity is low.

As is clear from the above results, the fueganomycin group antibiotics are promising as antituberculous agents. The fueganomycin group antibiotic of the present invention can be produced, for example, by culturing a fueganomycin group antibiotic-producing bacterium belonging to the genus Streptomyces in a medium, producing and accumulating the fueganomycin group antibiotic, and collecting the resulting product.

A typical example of the fueganomycin group antibiotic-producing bacteria belonging to the genus Streptomyces is Streptomyces silatous MD227, which was isolated from the soil of Lake Kawaguchi, Yamanashi Prefecture in September 1972 at the Institute of Microbial Chemistry.
-A9 (StreptOmycescirratus M
D227-A9) (hereinafter referred to as "MD227-A9 strain").

) (Agency of Industrial Science and Technology, Institute of Microbial Technology, Accession No. 358
No. 6, FERM-PS). 3586). The mycological properties of MD227-A9 strain are shown below. 1. Morphology The MD227-A9 strain forms spiral aerial hyphae from branched basal hyphae, and no whorled branches are observed.

A mature spore chain consists of 10 or more spores, the size of the spores is about 0.6 to 0.8 x 1.0 to 1.2 microns, and the surface of the spores is smooth. 2. Regarding the description of growth state colors in various media, the standards shown in brackets are from the Color Harmony Manual of Container Corporation of America.
OnOf Decoration Erica's COlOrHarmOnyll
01) Sucrose/nitrate agar medium (cultivated at 27°C) using A. anllal) Brown-white to pick-white aerial mycelia grow loosely on the colorless growth, and no soluble pigments are observed.

2) Glucose-asparagine agar medium (cultured at 27°C)
Growth is colorless to pale yellow, no aerial mycelia are attached, and no soluble pigments are observed.

3) Glycerin-asparagine agar medium (ISP-1 medium 5, cultured at 270°C)
rROse') Pick Gray [6ge1R0seGray
] ~ Red-gray aerial mycelium grows on the plant, and the soluble pigment is only slightly brownish.

4) Starch/inorganic salt agar medium (ISP-1 medium 4, 27
0℃ culture) On the colorless to pale yellow growth, apply a light pick [5e
c. Dusty Peach]~Grows on light reddish brown aerial mycelium, and the soluble pigment is only slightly brownish.

5) Tyrosine agar medium (ISP-1 medium 7, cultured at 27°C) Light pick [7ec1R0seMist] - Pick ash [6ge1R]
0seGray] and produces a dark brown soluble pigment.

3) Nutrient agar medium (cultured at 27°C) Growth is pale yellow to brown, aerial mycelia do not attach, and brown soluble pigment is produced.

1) Yeast/malt agar medium (ISP-1 medium 2, 270
℃ culture) light yellow tea to yellow tea, apply a light pick [[7]
ec1R0seMist] ~ Pick Ash [6ge1R0s
eGray] ~Grows on reddish gray aerial mycelia, and no soluble pigments are observed.

3) Oatmeal agar medium (ISP-1 medium 3, 27°C
Culture) A light reddish brown aerial mycelium grows on the colorless growth,
No soluble pigments are observed.

(9) Glycerin/nitrate agar medium (cultured at 27°C) Brown-white aerial mycelium grows loosely on the colorless growth, and no soluble pigment is observed.

(Sub) Starch agar medium (27°C culture) Colorless to light yellow, or light pick to light reddish brown aerial mycelia are grown on the growing pale olive, and the soluble pigment is only slightly yellowish. be.

(Own) Malate-lime agar medium (cultured at 27°C) White aerial mycelium grows loosely on the colorless growth, and no soluble pigment is observed.

(Substitute) Cellulose (cultured at 27°C) Growth is colorless, no aerial mycelia are attached, and no soluble pigments are observed.

(Auto) Gelatin puncture culture In a simple gelatin medium (cultured at 20°C), white aerial mycelium grows loosely on the growing colorless to pale yellow tea, producing the soluble pigment of tea.

In glucose-peptone-gelatin medium (cultured at 27°C), the growth is grayish yellowish brown, no aerial mycelia are attached, and the soluble pigment is dark brown. (Own) Skimmed milk (cultured at 37°C) Growth is light yellow to yellowish brown, a few white aerial mycelia are attached, and light brown to brown soluble pigment is produced.

3. Physiological Properties (1) Growth Temperature Range Using glucose-asparagine agar, the results of tests at each temperature of 20°C, 24°C, 27°C, 30°C, 37°C, and 50°C showed that all temperatures except 50°C However, the optimum temperature is thought to be between 27°C and 30°C.

(2) Liquefaction of gelatin (glucose peptone gelatin medium, 27°C culture and 15% simple gelatin medium, 2
(Culture at 0°C) No liquefaction was observed in the case of simple gelatin medium.

In glucose-peptone-gelatin medium, after culturing 14
Liquefaction begins around the first day, and its effect is moderate to weak. (3) Hydrolysis of starch (starch/inorganic salt agar medium and starch agar medium, both cultured at 27°C) Water decomposition was observed from around 5 days after culture, and its effect was moderate to strong.

(4) Coagulation and peptonization of skimmed milk (skimmed milk, 37℃
Cultivation) Peptonization begins around the 10th day after culture without coagulation and is completed around the 14th day.

The effect is moderate to strong. (5) Production of melanin-like pigment (Trifton Yeast Pros, ISP-1 Medium 1, Peptone Yeast-Iron Agar, ISP-1 Medium 6;
Tyrosine agar 1SP and medium 7, all cultured at 27°C).

(6) Utilization of carbon sources (Pridham-Gotlieb agar medium, ISP-1 medium 9, 27°C culture) Glucose, L-arabinose, D-flag dose, sucrose, inositol, rhamnose, raffinose, D -Do not use mannitol.

D-xylose is probably not utilized. (7) Dissolution of malic acid lime (malic acid lime agar, cultured at 27°C) Malic acid lime around the growth is dissolved from around 10 days after culture, and its effect is moderate to strong.

(8) Nitrate reduction reaction (peptone water containing 1.0% sodium nitrate, SP-1 medium 8, cultured at 27°C) is positive.

To summarize the above properties, strain MD227-A9 belongs to the genus Streptomyces, the aerial hyphae are spirally formed, whorled branches are not observed, and the surface of the spores is smooth.

On the growth of colorless to light yellowish brown or yellowish brown in various media,
It grows on aerial mycelia of light pick to pick ash or light reddish brown color, and almost no soluble pigments are observed.

The melanin-like pigment is positive, and the proteolytic ability and starch hydrolyzability are moderate to strong. From these properties, MD227
- When searching for known bacterial species closely related to strain A9, the ISP description shows that Streptomyces
cescirratuslReference 1) International
nalJOurnalOfSystematicBac
terlOlOgyl vol. 22, p. 284, 1972;
Reference 2) TheJOnalOfAntiblOti
cs,. Ser. All 6 volumes, black 2, 59 pages, 1963
) and Streptomyces griseolabendus (St.
reptOmycesgriseOlavendusl
InternationalJournalOfSys
tematicBActerlOlOgyll Volume 9, 4
p. 34, 1969) *. Next, we actually obtained these two strains and compared them with the MD227-A9 strain, and the summary of the results is as follows. As seen in the table, strain MD227-A9 and Streptomyces silatus SP5479 are almost identical except for nitrate reduction reaction, milk coagulation, and D-xylose utilization.

The coagulability of milk produced by Streptomyces silatus is extremely weak, as described in literature (2).
Furthermore, the difference in the reduction reaction of nitrate is generally not considered to be very important, and the greatest difference is judged to be the usability of D-xylose.

On the other hand, Streptomyces griseolabendus ISP5
The 385 strain is characterized by the presence or absence of spiral formation, milk coagulation, and L.
- Differences are also observed in the availability of arabinose and D-flag doses. Among these differences, regarding spiral formation, Streptomyces griseolabendus has been described in the literature as having a hook-shaped or loop-shaped tip of the aerial hyphae, but in this comparative experiment, the ISP medium In the above, no spiral formation was observed, which is considered to be a major difference from the MD227-A9 strain, along with coagulation of milk and utilization of L-arabinose. From these points, MD227-A
The 9 strains are considered to be the most closely related species to Streptomyces silatus, and include Streptomyces silatus MD22.
It was identified as 71A9.

Actinomycetes tend to undergo mutations both artificially and naturally, and MD227-A9 here includes all of these mutant bacteria. These bacterial species also produce fueganomycin group antibiotics, and include all bacteria that are not clearly distinguishable from this bacterial species and its variants. To produce a fueganomycin group antibiotic using a fueganomycin group antibiotic-producing bacterium, the strain is first aerobically cultured in a medium containing nutrients that can be utilized by actinomycetes.

As a nutrient source, known ones that have been conventionally used for culturing actinomycetes can be used. For example, as a carbon source, glucose, starch, maltose, dextrin, shaken sugar, starch syrup (starch malt saccharide), soybean oil, etc. can be used alone or in combination.

Inorganic and organic nitrogen sources include ammonium chloride, ammonium sulfate, urea, ammonium nitrate, sodium nitrate,
Peptone, meat factory scratches, yeast factory scratches, dry yeast, corn steep liquor, soybean flour, cottonseed oil and gas, casamino acids, bacto soyton, solid vegetable protein, etc. can be used alone or in combination. Other inorganic salts such as common salt, magnesium sulfate, copper sulfate, iron sulfate, zinc sulfate, manganese chloride, calcium carbonate, and phosphates can be added as necessary to promote the growth of this bacteria and the production of feganomycin group antibiotics. Organic substances such as amino acids and inorganic substances can be appropriately added.
The most suitable culture method is a liquid culture method, especially a deep agitation culture method. It is desirable to culture at a culture temperature of 25° C. to 40° C. and at a neutral or slightly acidic pH. In liquid culture, when the culture is carried out for 3 to 10 days, the fueganomycino group antibiotics are produced and accumulated in the culture solution. When the production amount in the culture solution reaches the maximum, stop the culture, separate the bacterial cells,
The target product is purified and isolated from the obtained culture fluid. For the purification and isolation of this substance from the culture fluid, a separation and purification method generally used for isolating microbial metabolic products from the culture fluid is used.

Group 7 antibiotics of P. fuegani are highly soluble in water, but are insoluble or poorly soluble in general organic solvents such as methanol, ethanol, and acetone, and are purified using the method used to purify water-soluble basic substances. be exposed. Namely, cation exchange resin, Amberlite 8
Adsorption/desorption methods using XAD-2 and activated carbon powder, column chromatography using Cephadex G-10 and CM Cephadex 8C-25, and other methods can be used in appropriate combinations. For example, after adjusting the culture suspension to pH 6.5, it is adsorbed on Amberlite 8XAD-2, washed with water, eluted with 50% methanol, and the active fraction is concentrated and freeze-dried. The soluble portion of the obtained brownish coarse powder was removed with methanol, the insoluble matter was dried and dissolved in water, adsorbed on an activated carbon powder column, washed with water, and mixed with 0.1N hydrochloric acid:acetone (
1 volume: 1 volume),
, 9τ The obtained active fraction is neutralized with a weakly basic resin Dowex 44 (0H type) and then concentrated and freeze-dried to obtain a gray-brown coarse powder containing a feganomycin group antibiotic (mixture). Add a small amount of this to 0.05
When P is dissolved in saline solution and adsorbed on a column of CM Sephadex C-259, and concentration gradient elution is performed with a saline solution of 0.05M to 1.0M, P is dissolved in a concentration of 0.05M to 0.1M.
HG-DGPT. ．． PHG-D1 DeoxyPHG-D is PHG at around 0.4M, and PHG at around 0.5M.
-DR are respectively eluted. These are adsorbed onto Amberlite 8XAD-2, washed with water, desalted by elution with 50% methanol water, and freeze-dried. Each crude powder obtained here is dissolved in a small amount of water, adsorbed on a Sephadex G-10 column and developed with water to remove colored substances, and the active fraction is concentrated and freeze-dried. pale yellow pH
G-DGPT,. Dissolve the mixture of PHG-D1 deoxy PHG-D in a small amount of water and add CM Cephadex C-2.
Using a column of No. 5 and eluting with 0.05M saline, the pH
It is eluted in the order of G-DGPTlPHG-D1 deoxyPHG-D. Each active fraction is desalted using the method described above to obtain colorless powders. The method for producing the feganomycin group antibiotics of the present invention will be described below with reference to Examples.

Example 1 1% starch, 1% glucose, 1.
5%, dibasic potassium phosphate 0.1%, magnesium sulfate 0
．． 1%, salt 0.3%, copper sulfate 0.0007%, iron sulfate 0.00013%, manganese chloride 0.0008%, zinc sulfate 0.0002%, silicone KM-70 as antifoaming agent.
(Shin-Etsu Chemical): Soybean oil (local method) (1:1) 0.05%
, 120 ml of medium was autoclaved at 120°C for 20 minutes at pH 6.8, inoculated with one platinum loop of MD227-A9 strain (Feikoken Bacteria No. 3586),
Shaking culture was carried out at 180 rpm for 2 days at 180°C.

Separately, in the same Erlenmeyer flask as above, 5% starch syrup, 0.5% polypeptone, 0.5% meat scratches, and 0 yeast scratches.
3%, salt 0.3%, magnesium sulfate 0.1%, copper sulfate 0.0007%, iron sulfate 0,00013%, manganese chloride 0.0008%, zinc sulfate 0.0002%, silicon KM as an antifoaming agent. -70: Soybean oil (local law) (1:1)
120 ml of a medium was sterilized in an autoclave at 0.05% pH 6.8 at 120° C. for 20 minutes, 2 to 3 ml of the above culture solution was transplanted thereto, and cultured with shaking under the same conditions as above for 5 days. The culture solution has a pH of 6.5 and is strained at 10 f!
(Culture titer 25mcg titer/ml: However, PHG-
DRlOOOOmcg titer/Tfl9). Pass this slurry through a column packed with Amberlite 9XAD-211,
Feganomycin group antibiotics (mixture) were adsorbed, and after washing with water, the active fraction eluted with 50% methanol water was collected.
Concentrated under reduced pressure and lyophilized to dark brown powder 5,901
(38 mcg/~) was obtained. This was treated with 250ml of methanol to remove the soluble portion, and then the insoluble portion was dried under reduced pressure to obtain a brown coarse powder of 3.82y (55mcg titer/Tf!9). This was dissolved in 382 ml of water, adsorbed on a column of 100 ml of activated carbon powder, washed with water, and then
Elution was carried out with normal hydrochloric acid:acetone (1:1), and the active fraction was neutralized with Dowex 44 (0H-) and concentrated and lyophilized under reduced pressure. The resulting gray coarse powder 1.407 (90mc
g/Trl9) in 50ml of 0.05M saline,
Adsorb onto a 500ml column of CM Sephadex C-25 equilibrated with 0.05M saline, and
After elution with 500 ml of M saline, 0.3 and 0.7
Each sample was eluted using a linear concentration gradient method with 21 M saline solutions. 0.0
5M('PHG-DGPT,.PHG-D1 DeoxyP
A mixture of HG-D, PHGlO. around 0.4M. It was eluted in the order of PHG-DR around 5M.

Each active fraction was adsorbed onto Amberlite 9XAD-230ml, washed with water, and then desalted by elution with 50% methanol water. The obtained active fractions were concentrated and freeze-dried under reduced pressure to form pale yellowish-white powders. 87η (287m
cg titer/Wl9), colorless powder 10η (100mcg
A colorless powder of 50η (potency: 1000 mcg/immediately) was obtained. PHG-DGPT. with pale yellow color. P
Mixture 87T containing HG-D and deoxyPHG-D
! 19 was dissolved in 3 to 5 ml of water, passed through a column of 300 ml of Sephadex 8G-10 swollen with water to remove colored substances, the active fraction was collected and concentrated to 3 to 5 ml under reduced pressure, and immediately dissolved in 0.05 M sodium chloride in advance. Equilibrated with water [
It was adsorbed on a column of CM Sephadex C-25200me, eluted with 0.05M saline, and PHG-DG
P.T. ．． Solubility categories were obtained in the order of PHG-D1 deoxy PHG-D.

Next, the pure PHG-D is desalted by the desalting operation described above.
GPT2Omg (250mcg titer/7n9), PHG
Colorless powders of -D2OTIi9 (500mcg titer/1T19) and deoxyPHG-DlOη (500mcg titer/η) were obtained. Example 2 MD2 in the same manner as Example 1
Pre-culture solution 31? obtained by culturing the 27-A9 strain (Feikoken Bacteria No. 3586) Production medium 120,e described in Example 1
Transferred to a 2001 capacity stainless steel fermenter containing
Culture was carried out at 8° C. for 4 days using an aeration agitation method (number of revolutions: 380 revolutions/min, aeration rate: 1201/min).

Production concentration of fueganomycin group antibiotics (mixture), 1
A filter aid, Dai-8 Power Light (Daicalite Orient Co., Ltd.) 3k9, was added to culture solution 1001 containing 5 mcg titer/ml (PHG-DRlOOOmcg titer/~), and the bacterial cells were separated.

The pH of the slurry 801 was adjusted to 6.5 with 1N caustic soda, and the mixture was passed through an Amberlite XAD-2101 column to adsorb the target component mixture. 50% after washing column with water
Elution was carried out with methanol water, and the active fraction was collected and concentrated and lyophilized under reduced pressure to obtain an 80y dark brown coarse powder (13 mcg titer/wa). Next, mix this coarse powder 807 with methanol 31
After removing the soluble portion, the insoluble portion was dried under reduced pressure to obtain a dark brown coarse powder 40y (20 mcg titer/wa). Dissolve this powder in 800mj of water and dissolve the activated carbon powder in 1/2?
was passed through a column to adsorb the fueganomycin group antibiotic (mixture). After washing with water, 0.1N hydrochloric acid:acetone (1
．． , 8 volumes: 1 volume), and the active fraction was neutralized with Dowex 44 (0H), concentrated and lyophilized.

The obtained brown coarse powder 13y (50mcg titer/M9) was added to 200T of 0.05M saline solution! 11, preliminarily 0.0
CM Sephadex 8C253 equilibrated with 5M saline
1 column and eluted with 0.05M saline 61, then eluted with 61 each of 0.3M, 0.4M, and 0.5M saline in a stepwise wash. PHG- at 0.05M concentration
DGPT. PHG-D, a mixture of deoxyPHG-D,
PHG near 0.3-0.4M concentration, P at 0.5M concentration
Each component of HG-DR was eluted.

Each active fraction was desalted using the same desalting method ZZ as in Example 1, concentrated under reduced pressure, frozen, and dried to produce PHGDGPT. PHG-
D, pale yellowish-white mixture of deoxyPHG-D 45
0wa (366mcg titer/Tl9), PHG colorless powder 50w (100mcg titer/mk) and PHG-DR
250 mcg (potency 1000 mcg/w) of colorless powder was obtained.

Next, dissolve 450 liters of the pale yellow mixture in 20 ml of water.
, 9, Cephadex G pre-swollen with water
lOl. CM Sephadex was passed through a 5 l column to remove colored substances and the active fraction was concentrated under reduced pressure to 10-15 ml, which was immediately equilibrated with 0.05 M saline.
When adsorbed onto a C-2511 column and eluted with 0.05M saline, PHGDGPT. PHG-D, deoxyPH
It was eluted in the order of GD.

Each active fraction was desalted by the desalting operation described above, and pure PHG-DGPTl5Om' (250 mcg titer/
wa), PHG-Dl5O immediately (500mcg titer/η),
and deoxyPHG-D5Oη (500m0g titer/
A colorless powder of ヮ) was obtained.

[Brief explanation of the drawing]

Figure 1 shows the ultraviolet absorption spectra of Feganomycin, Feganomycin D1, Feganomycin DR, Feganomycin DGPT, and Deoxyfeganomycin D. 1 shows the infrared absorption spectra of Feganomycin D.

Claims (1)

[Claims] 1 General formula ▲ Numerical formula, chemical formula, table, etc. ▼ A fueganomycin group antibiotic represented by (indicates a prolyl-threonine residue).