Myxinol tetra-acetate was examined by both nuclear-magnetic-resonance and mass-spectral techniques. The results are compared with corresponding data for 5alpha-ranol tetra-acetate and 5alpha-cyprinol tetra-acetate. The structure deduced for myxinol tetra-acetate, 3beta,7alpha,16alpha,27-tetrahydroxy-5beta-cholestane, is in agreement with that simultaneously arrived at by Haslewood (1966).

نخستین گام در راستای تحلیل و ارزیابی ریسک‌های زنجیره تأمین شناسایی این ریسک‌ها است. روش‌های مرسوم بر اساس فیلترهای دستی یا خودکار داده‌­محور ارائه شده فیلتر به‌­دلیل محدودیت‌های نمونه‌گیری دارای مشکلات اعتبارسنجی هستند از طرف دیگر مبتنی داده، داده‌های ریسک که پیچیده مبهم هستند، عملکرد ضعیفی دارند. برای پرکرده خلل پژوهشی، پژوهش، چارچوبی تعاملی بین تحلیل‌­گر ماشین حجم وسیعی حوزه مواد غذایی با است...

In the title compound, [Cu(C(6)H(5)O(3))(C(18)H(15)P)(2)]·C(18)H(15)P·CH(3)OH, the pyran-4-one ring is appromimately planar (r.m.s deviation = 0.0138 Å), with the Cu(I) atom 0.451 (5) Å out of the plane. The Cu(I) atom has a distorted tetra-hedral coordination. The O-Cu-O angle is 80.07 (8)° and the P-Cu-P angle is 123.49 (3)°. The crystal packing is stablized by intra-molecular C-H⋯O inter-act...

In the title compound, C(32)H(19)BN(6)O(2), the B atom adopts a BON(3) tetra-hedral coordination geometry. In the crystal, pairs of mol-ecules are associated through aromatic π-π stacking inter-actions between the concave faces of the boronsubphthalocyanine fragments at a centroid-centroid distance of 3.4951 (19) Å and a weaker inter-action of the same type between the convex faces of the same ...

The title compound, C(24)H(46)N(4)O(8) (2+)·2Cl(-)·2H(2)O, was synthes-ized by the hydrolysis of tetra-ethyl 2,2',2'',2'''-(5,5,7,12,12,14-hexa-methyl-1,4,8,11-tetra-azacyclo-tetra-decane-1,4,8,11-tetra-yl) tetra-acetate in hydro-chloric acid solution. The crystal structure of the title compound consists of a 14-membered C(10)N(4) centrosymmetric cationic macrocycle which inter-acts with the ch...

Two types of porphyrin free base, meso-tetra(4-vinylphenyl)porphyrin and meso-tetra(4-stilbenyl)porphyrin, were synthesized and characterized. Metallation was achieved by insertion of MnCl24H2O. Oxidative electropolymerization of the manganese porphyrin monomers by cyclic scans would anchor the resulting materials on glassy carbon electrodes. It was found that both poly (manganese tetra(4-vinyl...

In the title Cu(I) compound, [Cu(C6H5N5)(C18H15P)2]BF4, the Cu(I) cation is N,N'-chelated by a 5-(pyridin-2-yl)-1H-tetra-zole ligand and coordinated by two triphenyl-phosphane ligands in a distorted tetra-hedral geometry. The tetra-zole and pyridine rings are essentially coplanar [dihedral angle = 4.1 (3)°]. The tetra-fluoridoborate anion links to the complex cation via an N-H⋯F hydrogen bond.

The article is devoted to hidden symmetries in long sequences of oligonucleotides of single stranded DNA. The notions of tetra-groups of oligonucleotides and also collective frequencies and collective probabilities of members of the tetra-groups are introduced to study hidden tetra-group regularities in mentioned sequences. Each of such tetra-group contains 4 members, each of which combines 4^(...

The title three-dimensional coordination polymer, [Cu(2)Cl(C(6)H(4)N(5))](n), is the product of the hydro-thermal reaction of CuCl(2)·2H(2)O and 5-(4-pyrid-yl)-1H-tetra-zole (4-Hptz). The two independent Cu(I) ions are coordinated in distorted tetra-hedral and distorted trigonal coordination environments. In the unique 5-(4-pyrid-yl)-1H-tetra-zolate ligand, the dihedral angle between the pyridi...

Four mol-ecular salts made from hexa-methyl-ene-tetra-minium and 2-chloro-4-nitro-benzoate have been synthesized and are reported, namely ammonium hexa-methyl-ene-tetra-minium bis-(2-chloro-4-nitro-benzoate), NH4+·C6H13N4+·2C7H3ClNO4-, (I), hexa-methyl-ene-tetra-minium hydrogen bis-(2-chloro-4-nitro-benzoate), 0.5C6H13N4+·C7H3.50ClNO4-, (II), hexa-methyl-ene-tetra-minium 2-chloro-4-nitro-benzoa...