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Biomedical subjects

V M Lynch

Publications and source records attributed to V M Lynch.

38 records · Page 3Linked to original sources
PubMed1988

Structure of [Mg(HO3PCH(C6H5)2)2].8H2O, a layered phosphonate salt.

Bis(hydrogen diphenylmethylphosphonato)-magnesium octahydrate, [Mg(C13H12O3P)2].8H2O. Mr = 662.85, triclinic, P1, a = 6.1051 (15), b = 8.8308(14), c = 15.312(3) A, alpha = 78.514(13), beta = 83.993(11), gamma = 75.772(15) degrees, V = 782.8(3) A3, Z = 1, Dx = 1.41 g cm-3 (163 K), Mo K alpha, lambda = 0.71069 A, mu = 2.171 cm-1, F(000) = 350, T = 163 K, R = 0.0351 for 3749 reflections [F0 greater than or equal to 4 sigma(F0)]. The structure consists of alternating polar and nonpolar layers stacked along the crystallographic c axis. The polar layers contain Mg(H2O)26+ ions, water of hydration and the phosphonate O atoms, and the nonpolar layers contain the benzhydryl groups. Two-dimensional hydrogen-bonding networks link Mg(H2O)26+ and the water of hydration to the phosphonate O atoms. The shortest hydrogen bonds in the structure, 1.68(2) A, connect the P-OH H atom and the water of hydration. Slightly longer contacts [1.79(2), 1.85(2), 1.91(2), 1.92(2) A] connect the phosphonate O atoms (O1 and O3) to the H atoms of the Mg(H2O)26+ group. The coordination environment of the Mg atom is a very nearly regular octahedron of water O atoms.

Chemical Phenomena↗
PubMed1988

Structure of the ABC ring synthon of dendrobine.

(1R,4S,8S,11R)-11-Methyl-3-[(R)-alpha-phenyl-ethyl]-3- azatricyclo[6.2.1.0(4.11)]undec-5-en-2-one, C19H23NO, Mr = 281.40, orthorhombic, P2(1)2(1)2(1), a = 9.534 (2), b = 11.055 (4), C = 14.372 (4) A, V = 1514.8 (8) A, Z = 4, Dx = 1.23 (163 K), Dm = 1.15 g cm-3 (295 K), lambda(Mo K alpha) = 0.71069 A, mu = 0.702 cm-1, F(000) = 608, T = 163 K, R = 0.0387 for 2310 reflections. The absolute configuration is assigned on the basis of internal comparison with the alpha-methylbenzylamine moiety. The tricyclic ring system is concave. The N appears to be sp2 hybridized [N is 0.0661 (1) A from the plane through C atoms bound to it] and conjugated through the carbonyl group [short C-N bond [1.351 (2) A]]. Ring strain appears to cause a slight increase in the C-C bond lengths of the center atom of the tricyclic ring system. The average bond length from this atom to the three other ring C atoms is 1.557 (1) A while the average bond length for all other sp3-C to sp3-C bonds is 1.529 (1) A.

Alkaloids↗