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Two compounds having biological activities, 3-indolethanol and (L-phe, L-pro) diketopiperazine, have been isolated from a new filamentous soil bacterium called Streptomyces sp. US24 strain.To our knowledge, it is the first time that these two active molecules are described from Streptomyces species. The structures of these two compounds were established on the basis on their spectral data such as IR, as well as NMR 1D and 2D (COSY, HMQC, HMBC).In the course of screening of new biological active molecules, several research studies are currently oriented towards isolation of new Streptomyces bacteria from different soil and water samples. In fact, the soil bacteria Streptomyces produce a large number of secondary metabolites, including antibiotics, antifungals, immunosuppressants, herbicides, enzyme inhibitors, and other physiologically active substances [1]. These active molecules are generally extracellular. Their isolation in highest purity from the complex fermentation broth and their structure elucidation needs the application of a combination of various separation steps and several spectroscopic methods.We have previously reported the isolation from Tunisian soil of a new actinomycete strain called Streptomyces sp. US 24 producing biological activities [2]. We report here the purification as well as the structure determination of two active molecules from this new bacterium.The Streptomyces sp. US 24 strain was cultivated in tryptic soy broth (TSB) medium supplemented with starch at 1% (w/v) and trace mineral oligoelements [2]. After various purification steps of the resulting crude extract, two natural compoun ds having biological activities were purified and characterized: 3-indolethanol and (L-phe, L-pro) diketopiperazine. 3-Indolethanol.This molecule belongs to the tryptophol family and possesses biological activities against Grampositive bacteria and Candida albicans [3]. It should be noticed that many indolethanol derivatives having interesting applications were prepared by semisynthetic pathways [4,5].The structure of this compound was determined by a combination of one-and two-dimensional spectra (COSY, HMQC, HMBC). The 1 H, 13 C, and HMBC NMR data of this molecule are summarized in Table 1. The EI-MS gave the molecular ion peak [M + ] at m/z 161 which allowed identifying the molecular formula as C 10 H 11 NO combining with the NMR data.The 1 H-NMR spectrum showed two signals with chemical shifts 3.05 and 3.93 ppm for the two CH 2 groups and one signal at 8.09 ppm attributed to the N-H proton.The 13 C NMR spectrum contains 10 signals, the first at 28.7 ppm and the second at 62.5 ppm. These two signals were attributed to the two CH 2 carbons (C-8 and C-9). In the region from 110 to 140 ppm we noted the presence of 8 signals attributed to the different carbon atoms.

The structure and thermal behavior are key factors that influence the functional response of Ni–Mn–Sn alloys. The present study reports the production as well as the structure and thermal analysis of melt-spun (solidification rate: 40 ms−1) Ni50 Mn50−xSnx (x = 10, 11, 12 and 13 at.%) alloys. X-ray diffraction measurements were performed at room temperature. The austenite state has an L21 structure, whereas the structure of the martensite is 7M or 10M (depending on the Sn/Mn percentage). Furthermore, the structural martensitic transformation was detected by differential scanning calorimetry (DSC). As expected, upon increasing the Sn content, the characteristic temperatures also increase. The same tendency is detected in the thermodynamic parameters (entropy and enthalpy). The e/a control allows the development production of alloys with a transformation close to room temperature.