for trapoxin B, by X-ray analysis, mass spectrometric, NMR and chemical studies.

PA48009,a lanthionine-containing peptide antibiotic was isolated from the culture broth of Streptoverticillium griseoverticillatum PA-48009, and identified as duramycin. Determination of the structure using both Edmandegradations and 2D NMR spectroscopy showed the need to revise the structure of duramycin given in literature. Duramycin (PA48009) was different from lanthiopeptin (Ro 09-0198, cinnamycin) only by a Lys/Arg exchange at position 2.During screening of new biologically active compounds, PA48009 (1), a lanthionine-containing peptide antibiotic, was isolated from the fermentation broth of Streptoverticillium griseoverticillatum PA-48009. It exhibited weak antimicrobial activity against Gram-positive organisms. Several lanthionine-containing peptide antibiotics have been reported already1~n). Recent development of NMRmethodology and instrumentation12 '13) make it possible to analyze NMRspectra and to determine the conformation of small proteins and oligopeptides. The structure of Ro 09-0198 was reported by Kessler et al.lt8\ but the reported structure showed some discrepancies with that of lanthiopeptin (3) ( = Ro 09-0198) reported by Wakamiya et al.3). Weconsidered that this problem had arisen from the difficulty in discriminating the amino acid residue as Ala or Phe in the sequence analysis using NMR. Therefore, we employed both NMRarid Edmandegradation methods to analyze the structure of 1. The discrimination of the Phe residue from the Ala residue was possible with Edmandegradation, and the sulfide bridges in the lanthionine (Lan) and methyllanthionine (MeLan) moiety and the NHbridge in the lysinoalanine (LysAla) moiety were easily determined by analyzing the NOESYspectra. As PA48009 (1) was identified as duramycin1'2) by physical measurements, wereport here the revised structure of duramycin (1) as shownin Fig. 1.

Cinatrins A, B, Cl5 C2 and C3, a family of phospholipase A2 inhibitors were isolated from the fermentation broth of Circinotrichum falcatisporum RF-641. They were found to be novel spiro-y-dilactones and y-lactones derived from 1 ,2,3,5-tetra or 1 ,2,3(or l ,2,4)-trihydroxypentadecane-1,2,3-tricarboxylic acids. Structures were elucidated by MSand NMRstudies and chemical transformations. The structure of cinatrin C3 was confirmed by X-ray crystallographic analysis, and its absolute configuration was determined by comparison of the CDspectra with related compounds.In a screening program for unique microbial products with pharmacological activity, the phospholipase A2 (PLA2) inhibitors cinatrins A (la), B (2a), Cx (3a), C2 (4a) and C3 (5a) were isolated from the fermentation broth of Circinotrichumfalcatisporum strain RF-641. The taxonomy, fermentation, isolation, physico-chemical properties and structures of cinatrin congeners are described in this paper. The biological properties are reported in a companionpaper.1} Taxonomy Strain RF-641 does not show typical morphological properties on agar media, and the properties shown on a leaf of Indian-rubber-tree (Ficus elastica) are described. Colonies are punctiform to effused, dark brown to black, hairy, and composed of dark, branched and anastomosing hyphae bearing setae and sporogenous cells. Setae arising from dark brown, thick-walled and swollen cells of the superficial mycelium, are numerous, simple, erect, thick-walled, sparsely, and indistinctly septate, roughened, dark brown, opaque, darker near the base, paler towards the apex which is circinate or spirally twisted. Sporogenouscells are numerous, arising laterally on the superficial hyphae, obclavate to lageniform, thin-walled, subhyaline. Conidia are adherent, persisting at the bases of the setae in the form of a whitish pellicle, falcate with acute ends, 18.5~20.0 x X.l^va. Based on the taxonomic properties described above, strain RF-641 was identified as Circinotrichum falcatisporum Pirozynsky (1962).2) Strain RF-641 has been deposited at the Fermentation Research Institute, Agency of Industrial Science and Technology, Japan, under the accession No. FERM P-10681. FermentationA slant culture of strain RF-641 was inoculated into a seed medium (100ml) containing Polypepton 1.0%, glucose 2.0%, beef extract 0.3%, yeast extract 0.2%, NaCl 0.1%, and tap water (pH 7.0) in a 500-ml Sakaguchi flask, and cultured at 28°C for 72 hours on a rotary shaker at 120 rpm. The seed culture was used at the rate of4% to inoculate 100ml of the production mediumin each of one hundred 500-ml Erlenmeyer flasks and cultivation was carried out at 28°C for 96 hours under agitation at 180rpm. The

New inhibitors of aldose reductase, designated salfredins A3, A4, A7, Cl5 C2, C3 and Bll5 were isolated from the fermentation broth of Crucibulum sp. RF-3817 by successive purification procedures of solvent extraction, silica gel column chromatographies and reverse-phase HPLC.Their structures were established by spectroscopic methods, including UV, SI-MS and NMR. The structures of salfredins A4 and B1 ]L were confirmed by X-ray crystallographic analysis.Aldose reductase (Alditol:NADP+ oxidoreductase, EC1.1.1.21) plays a key role in the "polyol pathway", and inhibition of this enzyme represents a new pharmacological approach towards the treatment of certain chronic complications of diabetes mellitus1~3).In a screening program for unique microbial products with pharmacological activity, new aldose reductase inhibitors4' 5), designated as salfredins A3 (la), A4 (2a), A7 (3a), Ci (4a), C2 (5a), C3 (6a) and B1X (7a), were isolated from the fermentation broth of Crucibulum sp. RF-3817. The taxonomy, fermentation, isolation, physico-chemical properties and structures of salfredin congeners are described in this paper. Their biological properties will be reported in a following paper (in preparation). TaxonomyThe strain RF-3817 was isolated as follows. First, peridioles within the peridium formed on a rotten wood block were immersed in a solution of sodium hypochlorite for one minute to sterilize the surface of the peridioles. Next, the peridioles were washed with sterile water and the basidiospores formed within the peridioles were placed on an appropriate mediumto isolate the strain. On the hyphae of the strain grown on the medium,clamp connections were observed, the width of each hypha being 1 to 5/mi. The peridium of the strain formed on the rotten wood block is pyriform, 5 to 8mm in height, 4 to 6mm in diameter, and has an ocher color. In the upper portion of the peridium, there is an epiphragm having a pale yellowish-white color, which will dehisce when matured.Within the peridium are lenticular peridioles. The peridioles, 1 to 1.5mm in size, are attached by funiculi to the inner wall of the peridium. Within the peridioles, basidiospores, 3 to 5 by 7 to 10fim, are formed. These properties were compared with the characteristics of other genera belonging to the order Nidulariales,

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