Iridomyrmex humilis

Akita and Ohta disclosed one of the earliest Sonogashira reactions of chloropyrazines and their A-oxides [24, 25]. The union of 2-chloro-3,6-dimethylpyrazine (23) and phenylacetylene led to 2,5-dimethyl-3-phenylethynylpyrazine (29). Subsequent Lindlar reduction of adduct 29 then delivered (Z)-2,5-dimethyl-3-styrylpyrazine (30), a natural product isolated from mandibular gland secretion of the Argentine ants, Iridomyrmex humilis. 

The characterization of tran, fraws-dolichodial (118) from Iridomyrmex humilis has been reported (c/. Vol. 6, p. 25), and chrysomelidial (119) and plagiolactone (120 the assigned absolute stereochemistry is tentative) are present in the defensive secretion of Plagiodera versicolora. ... 

Chart 8.1.1 Isoprenoids (skeletons) widespread on land (5max=45, av=29 S/Hm x-0.60, av=0.47). Monoterp. men thane (Compositae, Ang. from temeperateand subtropical, not forested, areas and Bryoph. AY) thujane (Ang. AY) bomane camphor and bomeol (tropical and subtropical Lauraceae and Mediterranean Labiatae, Ang. AY) pinane (Ang. and Gymn. MI AY) iridoids (Ang. and Argentine ant, Iridomyrmex humilis Mayr., Ins. BR MI). 

Markin, G. P. (1970). Food distribution within laboratory colonies of argentine ant, Iridomyrmex humilis (Mayr). Insectes Sociaux 17 127-158. 

The structure for valerosidate is incorrect in the previous Report (Vol. 5, p. 17). A new valepotriate has been isolated from Valeriana officinalis and shown spectroscopically to be 7-epideacetylisovaltrate (103) 193 it is also shown to be related to didrovaltrate (104) stereochemically, but in view of the recently reported absolute configuration of didrovaltrate (104)192 this assignment must be questioned. The occurrence of iridoids in the Argentine ant Iridomyrmex humilis has been re-investigated.194... 

All of these components possess the molecular formula C10HJ6O2 (mw 168 amu). Among these, the former two compounds are the reduced form nepetalactones [5], which is the main component of catnip, Nepeta cataria (Labiatae), known as a favorite plant of cats in the United States. The latter two components are also present in the postbinary anal gland secretions of the Argentina ant Iridomyrmex humilis) and Iridomyrmex nitidus and work as defensive substances [6—8].Therefore, these Cjo compounds with such skeleton are sometimes called iridoids. 

Iridomyrmecin (1) and isoiridomyrmecin (44) are used by ants such as Iridomyrmex humilis, /. nitidis, and Doli-choderus scabridus as defensive compounds. These lactones also were found in Aphis polygama. Thus, the structures of the lacewing atb-actants correspond to the reduced forms of the defensive compounds of ants (Sakan et al., 1970). 

Pyrazine alkaloids (Fig. 37.11) are known to occur in both Dlants and insects. These alkaloids serve as warning and ilarm substances from Iridomyrmex humilis ( driisena-neisen ) and Ondontomachus species ( Stachelameisen )... 

Van Vorhis Key, S.E. T.C. Baker. 1982. Specificity of laboratory trail following by the Argentine ant, Iridomyrmex humilis (Mayr), to Z-9-hexadecenal, analogs, and gaster extracts. J. Chem. Ecol. 8 1057-1063. 

In 1949 Pavan isolated the substance he called iridomyrmecin from the Argentine ant Iridomyrmex humilis (now Linepithema humile). Iridomyrmecin, dolichodial and other monoterpenes with a methylcyclopen-tanoid structure are called iridoids (Figure 6.12). They act as defensive compounds in ants, stick insects, rove beetles and leaf beetle larvae. Some of the group (e.g. the isomer of nepetalactone shown in Figure 6.12) are also sex pheromones in aphids. Reaction of iridomyrmecin with... 

There has been much speculation regarding the bios5mthesis of the iridomyr-mecins (I and II), and three attractive routes whose feasibility has been demonstrated by labotatory syntheses have been outhned. Wolinsky et al. (1965) have stated their intention to try to distinguish through tracer experiments which if any of these routes is followed by Iridomyrmex humilis. 

---