ANTE Spectra

Fig. 12 (a) The absorption spectra of singlet excited anthracene ( ANT ) and anthracene cation radical (ANT+ ) obtained upon 25-ps laser excitation of anthracene in the presence of excess maleic anhydride (MA). (b) The authentic spectrum of singlet excited anthracene ( ANT ). Reproduced with permission from Ref. 212. 

Fig. 14 Transient absorption spectrum of anthracene cation radical (ANT+ ) obtained upon 30-ps laser excitation of the [ANT, OsOJ charge-transfer complex in dichloro-methane. The inset shows the authentic spectrum of ANT+ obtained by an independent (electrochemical) method. Reproduced with permission from Ref. 96b.

The Protos warfare on their Lept neighbors depended heavily on chemicals, but ants are by no means unique in making extensive use of chemicals for communication and warfare. From one-celled organisms to complex plants and animals, many living creatures do the same. As species develop over evolutionary time, it is relatively easy for them to adapt their cellular machinery to producing chemicals for communication, warfare, and other purposes. These chemicals facilitate the way of life of organisms spread all across the biological spectrum. 

The problem is much more difficult when the defensive compounds are distributed throughout the insect body and no clues are available as to which type of compounds are present. In this case, a H NMR spectrum on the insect total extract will usually not be helpful, and a reliable bioassay is needed to follow the biological activity through the fractionation process. Repellency bioassays using ants [9] or spiders [10] have been successfully used for this purpose. Chemotaxonomy can also be very helpful, as taxonomically related insects tend to produce the same kind of defensive chemicals. Thus, once the latter have been identified for a few species, the study of other species belonging to the same group is usually much simplified. A good example is provided by coc-... 

Actinidine (9a), found in an anal gland of dolichoderine ants and in the defensive secretions of rove beetles (Table I), was identified on the basis of gas chromatographic and mass spectral analysis and the UV spectrum. The mass... 

Figure 4. A comparison of SD influence spectra for a dipolar diatom in liquid acetonitrile. The left panel depicts the spectrum corresponding to a change in the solute-solvent LJ energy and the right panel to a change in electrostatic energy. The gray lines depict the subspectra due to the solute ant the solvent molecule with the largest influence coefficient. The results are from Ref". ...

Figure 11.12—Schematic ant optica path of a single beam spectrophotometer equipped with electronic regulation (Hitachi U-1000). Measurements in solution are often carried out at a fixed wavelength after a calibration curve has been plotted. The use of higher performance double beam UV/Visible spectrometers is not necessary for these measurements in which the spectrum is not recorded. On the other hand, quantitative measurements from mixtures represent a different type of analysis.

A trail pheromone of the Pharaoh ant was identified as 3-butyl-5-methylindolizidine of the stereochemistry given in (219) (75JHC289). Slaframine (220) is a metabolite isolated from Rhizoctonia leguminicola responsible for producing excessive salivation in cattle. A stereoselective synthesis was reported (73JOC3848). Swainsonine (221), a potent inhibitor of a-mannosidase, has been isolated from Swainsona caneszens. The stereochemistry was derived from the NMR spectrum (79AJC2257). 

Some dihydropyran-2-ones are natural products and mass spectrometry has proved to be a useful tool in structure elucidation. For example, massoilactone (147), which is secreted by formicine ants, was characterized by its mass spectrum. On electron impact, the alkyl group is readily cleaved generating an ion at m/e 97 (68AJC2819). This process parallels the behaviour of other simple lactones. 

Second-generation juvenoids incorporate more substantial structural departures from neotenin and are more resistant to metabolic and environmental degradation. Epiphenonane, 2-ethyl-3-[3-ethyl-5-(4-ethylphenoxy)-pent-3-en-yl] 2-methyloxirane (131), has a rat oral LD50 of 4000 mg/kg. It and similar juvenoids are used in China and Japan to prolong the last larval instar of the silkworm so that silk production is increased 10—15%. Fenoxycarb, ethyl [2-(4-phenoxyphenoxy)ethyl] carbamate (132) (mp 53°C, vp 0.0078 mPa at 20°C), is soluble in water to 6 mg/L. The rat oral LD50 is >16,800 mg/kg. Fenoxycarb has a wide spectrum of activity, interfering with the developmental processes of fleas, cockroaches, and ants. 

The venomous constituent of the cryptic thief ant, Solenopsis xenovenenum, has been identified as the 3-heptyl-5-methylpyrrolizidine (50) from its mass spectrum and the fact that a related pyrrolidine (51) has been isolated from another species of ant.47 This is the first reported occurrence of a 3,5-dialkyl-pyrrolizidine, and its structure was confirmed by synthesis. Reductive amination of the known triketone (52) with sodium cyanoborohydride and ammonium acetate gave a mixture of four isomers of 3-heptyl-5-methylpyrrolizidine, which were separated by preparative g.l.c. The stereochemistry of the ring-junction of each isomer was established from its i.r. and n.m.r. spectra. 

Cyfluthrin is a broad-spectrum nonsystemic insecticide used to control cockroaches, ants, termites, mosquitoes, flies, tobacco budworms, and common chewing and sucking insects of cotton, cereal, potatoes, and peanuts. It is also used effectively in the control of public health pests. 

Social insects appear to protect themselves by producing antibiotics [106]. Honey contains antimicrobial substances [107] and ants produce low molecular weight compounds with broad-spectrum activity [108]. 

Irgasan DP300. [Ciba-Geigy] Tiidosan broad-spectrum bacteiiostat for deodu -ant prods. 

Ants emit tiny amounts of chemicals called alarm pheromones to warn other ants (of the same species) of the presence of an enemy. Several of the components of the pheromone in one species have been identified, and two of their structures follow. Which compound has the infrared spectrum shown ... 

Tobramycin is one component (factor 6) of a mixture produced by fermentation of Streptomyces tenebrarius. Lacking the C-3 hydroxyl group, it is not a substrate for APH(3 )-1 and APH(3 )-II and so has an intrinsically broader spectrum than kanamycin. It is a substrate, however, for adenylation at C-2 by ANT(2 ) and acetylation at C-3 by AAC(3)-I and AAC(3)-II and at C-2 by AAC(2 ) (Fig. 38.26). It is widely used parenterally for difficult infections, especially those by gentamicin-resistant Pseudomonas aeruginosa. It is believed by some clinicians to be less toxic than gentamicin. 

---