Synthesis and biological evaluation of nectriatide derivatives, potentiators of amphotericin B activity.

Nectriatide 1a, a naturally occurring cyclic tetrapeptide, has been reported to a potentiator of amphotericin B (AmB) activity. In order to elucidate its structure-activity relationships, we synthesized nectriatide derivatives with different amino acids in solution-phase synthesis and evaluated AmB-potentiating activity against Candida albicans. Among them, C-and N-terminal protected linear peptides were found to show the most potent AmB-potentiating activity.

New potentiators of amphotericin B activity, shodoamides A to C produced by Pseudophialophora sp. BF-0158.

During our screening program for new potentiators of amphotericin B activity against Candida albicans, shodoamides A to C (1-3) were isolated from a culture broth of the fungus Pseudophialophora sp. BF-0158 fermented under shaking conditions. A known congener named shodoamide D (4) in this paper was obtained from a culture broth of the BF-0158 strain fermented under static conditions.

New piericidin rhamnosides as potentiators of amphotericin B activity against Candida albicans produced by actinomycete strain TMPU-A0287.

Four new piericidin rhamnosides (2, 4-6) together with three known piericidins (1, 3, 7) were isolated from the culture broth of the unidentified actinomycete strain TMPU-A0287 as potentiators of antifungal amphotericin B (AmB) activity. The structures of piericidins were elucidated by spectroscopic analyses, including NMR and MS. Compounds 2 and 4-6 possessed a ketone at C-10 and one or two methoxy groups on the rhamnose in their structures.

Development of an in vivo-mimic silkworm infection model with Mycobacterium avium complex.

In vivo-mimic silkworm infection models with Mycobacterium avium and Mycobacterium intracellulare were newly established to evaluate the therapeutic effects of anti-M. avium complex (MAC) antibiotics. Silkworms raised at 37°C died within 72 hours of an injection of M.

Evaluation of Anti-Mycobacterial Compounds in a Silkworm Infection Model with .

Among four mycobacteria, , , BCG and () , we established a silkworm infection assay with . When silkworms (fifth-instar larvae, = 5) were infected through the hemolymph with (7.5 × 10 CFU/larva) and bred at 37 °C, they all died around 40 h after injection.

Screening of Indonesian Edible Plants for Bioactive Constituents and a New Protein Tyrosine Phosphatase 1B Inhibitory Acylbenzene Derivative from Leaves of Indonesian Syzygium polyanthum.

Bioassay screening using Indonesian plants, such as traditional foods (vegetables, spices, and tea) and folk medicinal herbs, identified eight protein tyrosine phosphatase (PTP) 1B inhibitory and two antibacterial plants. The leaves of Syzygium polyanthum (Wight) Walp. were examined in more detail to define PTP1B inhibitory components, resulting in the isolation of a new active acylbenzene (1) along with four related congeners of 1 (2-5) and four oleanane triterpenes (6-9).

Antifungal trichothecene sesquiterpenes obtained from the culture broth of marine-derived Trichoderma cf. brevicompactum and their structure-activity relationship.

Two new trichothecene sesquiterpenes, trichobreols D (1) and E (2), were isolated from the culture broth of marine-derived Trichoderma cf. brevicompactum together with trichobreol A (3). The structures of 1 and 2 were assigned on the basis of their spectroscopic data.

Epipolythiodiketopiperazine and trichothecene derivatives from the NaI-containing fermentation of marine-derived Trichoderma cf. brevicompactum.

The marine-derived fungus Trichoderma sp. TPU199 (cf. Trichoderma brevicompactum) produces pretrichodermamide A (1) and gliovirin (2), which possess a rare type of epipolythiodiketopiperazine (ETP) structure with a disulfide bridge between the α- and β-positions of two amino acid residues.

Polyketide glycosides phialotides A to H, new potentiators of amphotericin B activity, produced by Pseudophialophora sp. BF-0158.

Eight new potentiators of antifungal amphotericin B (AmB) activity, phialotides A to H, were isolated from the fermentation broths of the rare fungus Pseudophialophora sp. BF-0158. The structures of phialotides were elucidated by spectroscopic analyses, including NMR and MS, and degradation studies.

Nectriatide, a Potentiator of Amphotericin B Activity from sp. BF-0114.

A new compound, designated nectriatide (), was isolated as a potentiator of amphotericin B (AmB) activity against from the culture broth of sp. BF-0114. This structure was elucidated based on spectroscopic analyses (1D and 2D NMR data), chemical methods, and total synthesis.

Total Synthesis and Absolute Configuration of Simpotentin, a Potentiator of Amphotericin B Activity.

The total synthesis of simpotentin (), a new potentiator of amphotericin B activity against , was achieved. Our research results enabled the access of all stereoisomers of and the elucidation of the unknown absolute configuration of . Furthermore, one of the stereoisomers is a better amphotericin B potentiator than and is an excellent lead compound for the development of a novel amphotericin B potentiator.

Simpotentin, a new potentiator of amphotericin B activity against Candida albicans, produced by Simplicillium minatense FKI-4981.

Simpotentin, a new potentiator of amphotericin B activity against Candida albicans and Cryptococcus neoformans, was isolated from the culture broth of Simplicillium minatense FKI-4981 by Diaion HP-20 column chromatography, centrifugal partition chromatography, and preparative HPLC. The structure of simpotentin was elucidated by spectroscopic analyses including NMR and MS. The compound has a mannose core to which two medium-chain fatty acids are linked.

Anti-Mycobacterium activity of microbial peptides in a silkworm infection model with Mycobacterium smegmatis.

An in vivo-mimic silkworm infection model with Mycobacterium smegmatis was established. When silkworms were raised at 37 °C following an injection of M. smegmatis cells (1.