Rhizobium meliloti produces a family of sulfated lipooligosaccharides exhibiting different degrees of plant host specificity (nod ABSTRACTWe have shown that a Rhizobium meliloi strain overexpressing nodulation genes excreted high amounts of a family of N-acylated and 6-0-sulfated N-acetyl-fi-1,4-Dglucosamine penta-, tetra-, and trisaccharide Nod factors.Either a C16:2 or a C16:3 acyl chain is attached to the nonre-

By the reaction of Vilsmeier salts, derived from tetra-alkylureas or from tetra-alkylthioureas, with primary aliphatic amines, a series of sterically hindered penta-alkyl guanidines has been prepared. 2-t-Butyl-l',1',3",3"-tetramethyIguanidine and pentaisopropylguanidine combine ease of preparation with a range of resistance to alkylating agents. Preliminary experiments indicate that these inexpensive bases will be useful in organic synthesis.

Sinefungin l a and 6-epi-sinefungin 1 b have been prepared from adenosine and L-aspartic acid. The key step in the synthesis was the coupling of the radical derived from 14 with the unsaturated amide 13. The latter was obtained by a radical reaction from L-aspartic acid and olefin 11. Thus the carbon skeleton is constructed in two radical coupling reactions.Paper 0/05804A

The ability of D‐6‐deoxy‐myo‐inositol 1,4,5‐trisphosphate [6‐deoxy‐Ins(1,4,5)P3], a synthetic analogue of the second messenger D‐myo‐inositol 1,4,5‐trisphosphate [Ins(1,4,5)P3], to mobilise intracellular Ca2+ stores in permeabilised SH‐SY5Y neuroblastoma cells was investigated. 6‐Deoxy‐Ins(1,4,5)P3 was a full agonist (EC30 = 6.4 μM), but was some 70‐fold less potent than Ins (1,4,5)P3 (EC30 = 0.09 μM), indicating that the 6‐hydroxyl group of Ins(1,4,5)P3 is most important for receptor binding and stimulation of Ca2+ release, but is not an essential structural feature. 6‐Deoxy‐Ins(1,4,5)P3 was not a substrate for Ins (1,4,5)P3 5‐Phosphatase, but inhibited both the hydrolysis of 5‐[22P] + Ins (1,4,5)P3 (K 1 76 μM) and the phosphorylation of [3H]Ins(1,4,5)P3 (apparent K 1 5.7 μM) 6‐Deoxy‐Ins (1,4,5)P3 mobilized Ca2+ with different kinetics to Ins(1,4,5)P3, indicating that it is probably a substrate for Ins(1,4,5)P3 3‐kinase.

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