Chalcogenide derivatives of three aminomethylphosphines: P(CH2N(CH2CH2)2NCH3)3 (1), P(CH2N(CH2CH2)2NCH2CH3)3 (2) and P(CH2N(CH2CH2)2O)3 (3) were prepared: oxides--OP(CH2N(CH2CH2)2NCH3)3 (4), OP(CH2N(CH2CH2)2NCH2CH3)3 (5), OP(CH2N(CH2CH2)2O)3 (6), sulfides--SP(CH2N(CH2CH2)2NCH3)3 (7), SP(CH2N(CH2CH2)2NCH2CH3)3 (8), SP(CH2N(CH2CH2)2O)3 (9) and selenides--SeP(CH2N(CH2CH2)2NCH3)3 (10), SeP(CH2N(CH2CH2)2NCH2CH3)3 (11), SeP(CH2N(CH2CH2)2O)3 (12). The spectroscopic NMR analyses, DFT (B3LYP/6-31G**) calculations together with crystallographic studies of compounds 5, 6, 9 and 12 demonstrate that the structures and spectroscopic properties are strongly influenced by the chalcogen atom and not entirely contingent on aliphatic rings in the molecules. TEPs (Tolman's electronic parameters), estimated with DFT methods equal 2059.7 cm(-1) for 1, 2059.8 cm(-1) for 2 and 2061.2 cm(-1) for 3. These values are similar to TEPs estimated experimentally for other aminomethylphosphines. Phosphines 1, 2 and 3, despite very large Tolman cone angles show rather low influence of molecular geometry on their electronic properties: S4' (symmetric deformation coordinate) (59.8-64.8) and S4 (63.4-63.7) parameters are moderate. Suresh's steric effect (S(eff)) parameters for phosphines 1, 2 and 3 (2.70, 2.73 and 2.66, respectively) indicate minor electron-donating effect. Electronic effect (E(eff)) parameters (4.92, 5.21 and -0.40, respectively) can be easily modified by changing the substituents. 1J(SeP) coupling constants in the selenides are low (10: 707.5 11: 707.5 12: 709.8 Hz), but do not correlate with the TEP values in a way typical for aliphatic phosphines. The examined compounds do not show mutagenic properties and their potential toxicity is low, which is relevant in the context of their possible medical applications.

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Restriction fragment length polymorphism (RFLP) patterns of PCR-amplified ribosomal RNA gene fragments (rDNA) and randomly amplified polymorphic DNA (RAPD) were applied for the analysis of 15 brewing and 6 related yeast strains of the genus Saccharomyces. One five-base (ScrFI) and two four-base cutting (HaeIII, MspI) restriction enzymes were used. The primers 21 and M13 core sequence were selected for RAPD analysis. PCR-RFLP rDNA analysis with HaeIII, ScrFI and MspI differentiated the strains tested into four, five and four types of patterns, respectively and the analyses of the profiles showed 100% homology, between the yeast strains. One strain was an exception. Homological groups were observed for strains used in breweries globally, from a local production strain and from the isolates identified as S. cerevisiae. Using RAPD analysis, and according to discrete differences in the profiles, it was possible to divide twenty one strains into 15 and 20 groups with primer 21 and M13 respectively. RFLP-PCR rDNA analysis was used to show similarities in closely related brewing strains, while RAPD analysis was used for differentiation of strains.