Triterpanes

The main triterpanes in Russian petroleum are C27-35 17aH-hopanes. ... 

Hills, I. R., Whitehead, E. V., Triterpanes in Optically Active Petro-... 

Sterols have been identified from a 2000-year old marine sediment (283) and both steranes and pen-tacyclic triterpanes from the Green River oil-shale of Eocene age (285-... 

Optically active triterpanes have been identified from a number of crude oils (65, 81, 289). Steranes have long been known in petroleum (290) and optically active varieties identified from some crude oils (291). 

W. E., An Optically Active Triterpane, Gammacerane in Green River, Colorado, Oil Shale Bitumen, Chem. Commun. (1966), 752. 

The structures of triterpanes D (166)126 and H (167),127 from Nigerian crude oil, have been established by X-ray analysis. Dryocrassol (168), from the rhizomes of Polypodium leucotomos,12H is the C-22 epimer of neriifoliol. 

The compounds detected in the mass range 398-454 in B3, BBl, BB2, and POW extracts appear to be pentacyclic triterpanes since all have prominent m/e 149, 177, 191, and 205 peaks (1 ). When selected ion profiles are compared, WYOl extract shows no m/e 191 peaks for GC retention times in the pentacyclic triterpane region. The BB coal extracts, B3, ALBl and POWl all have numerous small peaks that are probably triterpenoids. Some of these gave appreciable GC FID responses and good mass spectra. 

The spectrum of m/e 398 is identical for ALBl and POWl extracts. The compound is not adiantane since the intensity of the m/e 191 peak is greater than 177, not similar (13). C27 - C31 Triterpanes, especially adiantane, C29, have been found in bituminous coal extracts (14). 

A number of hydrocarbon fractions from liquefaction products produced at GFETC from the coals studied here were investigated using selected ion profiles of the capillary GC/MS data. None of the hydrocarbon biological markers other than the acyclic alkanes already discussed were detected. There were no sesquiterpenes, sesquiter-panes, steranes, triterpanes or other cyclic terpenoids found. 

Several groups of hydrocarbon biological markers were identified in the coal extracts by mass spectrometry using selected ion scans. n-Alkanes, pristane, sesquiterpenes, several tricyclic alkanes and pentacyclic triterpanes with molecular weights from 398 to 454 were detected. 

Figure 15 shows isometric maps of Loveridge and Hiawatha coals and Noonan lignite. Shown on these maps are the mass chromatograms of m/e 191 and 206, and the molecular ions masses corresponding to the C27, C28, C29, C30, and C31 pentacyclic triterpanes. 

Figure 14. The m/e 191 mass chromatograms showing triterpane profiles of five U.S, coals...

Figure 15. Isometric map of three coals showing the relative importance of triterpanes to sesquiterpanes to aromatics...

Normal and branched alkanes, benzene-alkylbenzenes, copaene, cadalene, phenols, sesquiterpanes, and pentacyclic triterpanes decrease in relative concentration with the maturity of the coal. 

Grantham P. J., Pesthwma J. and Baak A. (1983) Triterpanes in a number of Far-Eastern crude oils. In Advances in Organic Geochemistry 1981 (eds. M. Bjoroy et al.). Wiley, New York, pp. 675-683. 

Henderson W., WoUrab V., and Eglinton G. (1969) Identification of steranes and triterpanes from a geological source by capillary gas hquid chromatography and mass spectrometry. In Advances in Organic Geochemistry 1968 (eds. P. A. Schenck and 1. Havenaar). Pergamon, London, pp. 181-207. 

Requejo A. G. (1992) Quantitative analysis of triterpane and sterane biomarkers methodology and applications in molecular maturity studies. In Biological Markers in Sediments and Petroleum (eds. J. M. Moldowan, P. Albrecht, and R. P. Philp). Prentice Hall, Englewood Cliffs, NJ, pp. 223 -240. 

Grantham P. J., Posthuma J., and DeGroot K. (1980) Variation and significance of the C27 and C28 triterpane content of a North Sea core and various North Sea crude oils. In Advances in Organic Geochemistry 1979 (eds. A. G. Douglas and J. R. Maxwell). Pergamon, Oxford, pp. 29-38. 

Pratt L. M., Summons R. E., and Hieshima G. B. (1991) Sterane and triterpane biomarkers in the Precambrian Nonesuch Formation, North American Midcontinent Rift. Geochim. Cosmochim. Acta 55, 911—916. 

A very comprehensive analysis of hydrocarbons (linear, acyclic and cyclic - steranes, hopanes etc.- isoprenoids) carboxylic acids, aldehydes, ketones and amines of the Vale do Paraiba and Marau oil shales was made by Chicarelli (27). An extremely careful quantitative and qualitative analysis of hydrocarbons (n-, iso-and anteiso-paraffins, isoprenoids, steranes and triterpanes) and carboxylic acids of Irati oil shale was presented by Carvalhaes (28). Nooner Oro (29) also reported data on the hydrocarbons pres ent in the Irati Formation. Polycyclic aromatic hydrocarbons in I-rati were determined by Youngblood Blumer (40). 

Cyclic Alkanes. In the cyclic fraction the following polycyclic isoprenoid compounds were identified (4) 27 29 steranes> methyl-C2g sterane> C 7 32 Pentacyclic triterpanes of hopane type (except C ft), anathe bicyclic tetraterpane perhydro-8-caro-tane (Table IIJ. 

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