3-(Pyrrole-2?-carboxamido)propanoic acid I has been synthesized from the reaction of β-alanine methyl ester with 2-trichloroacetylpyrrole followed by saponifying and acidating in 85.4% yield, and the crystal structure of 3-(pyrrole-2?-carboxamido)propanoic acid· (1/2)H2O (C8H11N2O3.5, Mr = 191.19) was obtained and determined by X-ray diffraction method. The crystal is of monoclinic, space group C2/c with a = 19.010(4), b = 8.3515(17), c = 13.788(3) ?, β = 125.88(3)o, V = 1773.6(6) ?3, Z = 8, Dc = 1.432 g/cm3, λ = 0.71073 ?, μ(MoKα) = 0.114 mm?1 and F(000) = 768. The structure was refined to R = 0.0354 and wR = 0.0942 for 1642 observed reflections with I > 2σ(I). It is revealed that the title compound has one pyrrole ring and one propionic acid subchain linked by an amido bond at C(4), and there are 8 molecules of com- pound I and 4 crystal water molecules in each unit cell. The supramolecular layers are stabilized by the hydrogen bonds of N(2) H…O(2), N(1) H…O(4), O(4) H(1W)…O(2) and O(3) H…O(1).
Two compositions,a pure ceramide and a sterol mixture,were isolated from the ethylacetate phase of ethanol extract of the Hypnea Charoides Lamx,collected from the South China Sea.The ceramide was identified by spectroscopic analysis as N-(2’hydroxytetracosyl)-1,3,4-trihydroxy-2-am ino-octadecane;The six sterols were detected by gas chromatography/mass spectrometry,and their structures were confirmed by spectroscopic analysis as Ergost-5,22-dien-3-ol,Ergost-5-en-3-ol,Stigmasta-5,22-dien-3-ol,Cholesta-5,22-dien-3-ol,Cholesta-5-en-3-ol,Stigmasta-5-en-3-ol.
