New sesquiterpene hydroxylactones from Lactarius species

Four γ-hydroxybutenolide sesquiterpenes have been isolated from Lactarius scrobiculatus, L. blennius and L. pallidus. Their structures and absolute stereochemistry were determined by spectral data and by conversion to known compounds.     

l-3-(3-carboxyfuran-4-yl)alanine,a new amino acid from the mushroom Phyllotopsis nidulans

A new amino acid has been discovered in uncombined form in extracts of the fruiting bodies of the mushroom, Phyllotopsis nidulans. Chemical and spectroscopic data support formulation of the structure as l-3-(3-carboxyfuran-4-yl)alanine.     

15-hydroxyblennin A,a new lactarane-type sesquiterpene lactone isolated from Lactarius torminosus

15-Hydroxyblennin A, a new lactarane-type sesquiterpene lactone was isolated from Lactarius torminosus mushrooms. Through spectroscopic (IR, ¹H NMR, ¹³C NMR, MS, UV) investigation and comparison with data for other known lactaranolides its structure was deduced as 3.     

l-threo- and l-erythro-2-amino-3-hydroxyhex-4-ynoic acids: New amino acids from Tricholomopsis rutilans

2-Amino-3-hydroxyhex-4-ynoic acid, reported previously from Tricholomopsis rutilans, was shown to be a mixture of its threo- and erythro-forms. They were separated from each other and characterized by elementary analysis, optical rotation, TLC, IR, NMR spectra, catalytic hydrogenation, and by chemical synthesis. Their configurations were determined by the comparison of their hydrogenation products with known threo- and erythro-2-amino-3-hydroxyhexanoic acids.     

Stereochemistry of blennin A and blennin D from Lactarius blennius

From the ethanolic extract of Lactarius blennius, a new sesquiterpene blennin D (2-hydroxyblennin A) was isolated and its structure elucidated together with the stereochemistry of the already known blennin A. Treatment of blennin A mesylate with DBU afforded a compound with a new skeleton.     

Sesquiterpenes from Lactarius blennius

Six sesquiterpene lactones were isolated from Lactarius blennius. The structures of two new sesquiterpenes, blennin A and blennin B were determinated by spectroscopic methods and the structure of the seco-compound, blennin C, is revised. The two known furan sesquiterpenes and lactarorufin A were also identified.     

Clithioneine,an amino acid betaine from clitocybe acromelalga

A new amino acid betaine, clithioneine, was isolated from a poisonous mushroom Clitocybe acromelalga, and its structure was established on the basis of spectral analyses and chemical degradation studies.     

中国红菇属乳菇状亚组的三个新种

红菇属乳菇状亚组Russula subsect. Lactarioideae是一个形态特征较明显的类群,亚属内部分种类被认为是复合种。在对我国红菇属乳菇状亚组进行的分类学研究中,发现了3个新种：丝黄红菇Russula byssina、奶油色红菇R. cremicolor和白果红菇R. leucocarpa,均产自我国贵州省,生于针叶林下。基于形态详细观察和ITS序列系统发育分析的结果对其进行详细描述,对新种和近缘种间差异进行了比较和讨论,提供了新种与乳菇状亚组和淡孢亚组R. subsect. Pallidosporinae中近缘种的物种检索表。分子系统学结果显示奶油色红菇与Delica-Brevipes分支亲缘关系较近,白果红菇和丝黄红菇隶属于两个独立分支。     

The absolute configuration of the new amino acid 2-amino-4-methyl-hex-5-enoic acid from a new guinea Boletus

The absolute configuration of the 2-amino-4-methyl-hex-5-enoic acid isolated from Boletus was shown to be 2S, 4S, by an unambiguous synthesis of its dihydro derivative from 2S-(?)-2-methylbutan-1-ol.     

Two new species of Russula subgenus Compactae from Indian Himalaya based on morphology and molecular phylogenetic inferences

The identity of blackening Russula (R. subg. Compactae) from Indian Himalaya has since long remained a mystery and they are often called after their European look-alikes. Here, a combined approach including morphology and ITS phylogenetic inference resolved the identification of some of these taxa and revealed the discovery of two novel species. Thus, Russula ashihoi sp. nov., found under Abies in subalpine Himalaya, and R. indonigra sp. nov. occurring under Quercus in subtropical to temperate Himalaya are proposed herein with their morphological details, illustrations and ITS-based phylogeny. Similarities with allied taxa are also discussed.     

Tetrahydrolathyrine: A new amino acid from seeds of Lonchocarpus costaricensis

A new non-protein amino acid, tetrahydrolathyrine (2(S)-3(2-amino-1,4,5,6- tetrahydropyrimidin-4-yl)alanine), has been isolated from seeds of Lonchocarpus costaricensis.     

A chloro amino acid from Amanita solitaria

The mushroom Amanita solitaria contains in excess of 1000 ppm 2(S)-amino-4,5-hexadienoic acid (I), 300 ppm trans-2-amino-5-chloro-4-hexenoic acid (II), and a chloride ion concentration (2000 ppm) significantly greater than that found in other basidiomycetes. I can be converted into II in hydrochloric acid, but II is not an artifact of isolation.     

中国乳菇属的研究III一个采自西藏的新种

报道了一个采自西藏的乳菇属新种Lactarius imbricatus(翘鳞乳菇)。文中提供了拉丁文描述、英文描述并附线条图及孢子的电镜扫描照片。标本保存于中国科学院昆明植物所隐花植物标本馆(HKAS)和中国科学院微生物研究所菌物标本馆(HMAS)。     

A toxic amino acid, 2(S)3(R)-2-amino-3-hydroxypent-4-ynoic acid from the fungus Sclerotium rolfsii

An amino acid, lethal to New Hampshire chickens (LD₅₀, 150 mg/kg) was isolated from dried sclerotia of the fungus Sclerotium rolfsii (Sacc.). Purification of the rather unstable compound was effected on a cation exchange column by means of displacement chromatography and the amino acid was crystallised from 80% methanol. A structure was assigned to the compound on the basis of available chemical and physical data, namely 2(S),3(R)-2- amino-3-hydroxypent-4-ynoic acid. Confirmation of this structure was gained by direct and indirect synthetic procedures.     

Schizonellin A and B,new glycolipids from Schizonella melanogramma

Two new glycolipids, schizonellin A and B, were isolated from cultures of the smut fungus Schizonella melanogramma. Their structures were elucidated by chemical degradation and spectroscopic methods. The schizonellins are active against Gram-positive bacteria, as well as against some Gram-negative bacteria and some fungi. DNA-, RNA- and protein-syntheses in Ehrlich carcinoma ascitic cells are inhibited simultaneously after addition of the schizonellins. Strong haemolytic action on bovine erythrocytes was observed.     

The amino acid composition of gum exudates from Prosopis species

The amino acid compositions of the proteinaceous components of the gum exudates from Prosopis alba, P. chilensis, P. glandulosa, P. laevigata, P. torreyana and P. velutina, and for a sample of commercial gum mesquite, are presented. In agreement with data published previously for the polysaccharide components of their gums, only minor differences in composition are shown by these species. The amino acid compositions are characterized by very high proportions of hydroxyproline and by high proportions of proline and serine; these three amino acids account for 62.5% of those present in the gum from Prosopis velutina. The amino acid compositions of these Prosopis gums are remarkably similar to that established recently for the gum from Acacia senegal (gum arabic).     

A new triterpenic acid from the wood rotting fungi

A new triterpenic acid, assigned the trivial name polyporenic acid D, has been isolated from the wood rotting fungus Polyporus officinalis. It has been shown to have the structure 3α-hydroxy-4,4,14α-trimethyl-5α-ergosta-8, 24(28)-dien-26-oic acid.     

Sesquiterpenes from Russula sardonia

Three new sesquiterpenes, furanether A, furosardonin A and sardonialactone A (7-hydroxyblennin A), together with lactaral, vellerolactone, two known furan alcohols, lactarorufin A and cerevisterol, were isolated from Russula sardonia. Structures and stereochemistry were elucidated by spectral data and correlation to known compounds by chemical transformations.     

A C-formylated azulene from Lactarius deterrimus

1-Formyl-4-methyl-7-isopropyl azulene (11,12-dihydro-lactaroviolin) was characterized from Lactarius deterrimus together with other known compounds.     

A new cyclolinopeptide containing nonproteinaceous amino acid N-methyl-4-aminoproline

Summary We have found that besides the known cyclolinopeptides A (CLA) and B (CLB), there is a new cyclic peptide in linseed mill cake that we have named CLX. Its composition is very similar to that of CLA, a cyclic peptide with a distinct immunosuppressive activity. The sequence of this peptide has been established ascyclo(PPFFILLX), where X is a non-proteinaceous amino acid,N-methyl-4-aminoproline. this amino acid substitutes for two amino acid residues of CLA, mimicking a dipeptide moiety with a nonplanarcis amide bond. The non-proteinaceous amino acid X may mimic a transition state of the peptide bond which exists in such processes as, e.g., PPIase-catalysedcis/trans amide-Pro bond isomerisation.