We describe a versatile novel approach for the synthesis of 2,4,6-trisubstituted pyrimidines on solid support. Thus, polymer-bound thiouronium salt 2 reacted in high yield in a cyclocondensation reaction with the acetylenic ketones 3 to form, after terr-butyl-ester cleavage, the polymer-bound carboxylic acids 4, which were cleaved by oxidation with 3-chloroperbenzoic acid and pyrrolidine to form the 2-pyrrolidinylpyrimidine-karboxylic acids 6a-e in high yields and purities without further purification (Scheme I ) . Alternatively, acid 4a was subjected to an Ugi four-component condensation which gave the polymer-bound Ugi products 9a-in good yields (Scheme 2). Multidirectional cleavage reaction of sulfone 8a with different nucleophiles resulted in the clean formation of pyrimidine-4-carboxamides 10-13 (Scheme 3). This strategy combines efficiently solid-phase chemistry with a multicomponent reaction and a multidirectional cleavage step to form highly diverse pyrimidines in a parallel array. As a part of an ongoing project, devoted toward the development of efficient methodologies for a parallel version of the combinatorial synthesis of different molecularily diverse heterocyclic systems on solid support, we have focused our attention on pyrimidine derivatives, due to the broad range of useful properties they display [22] [23], and developed a new and general synthetic route on solid support toward these potentially interesting compounds. Our strategy efficiently combines a versatile cyclocondensation reaction of acetylenic ketones with a polymer-bound isothiourea, to form polymer-bound 2-(alkylthio)-4,6-disubstituted pyrimidines, with the nucleophilic displacement reaction of the 2-sulfonyl group of pyrimidines [24] [25] by various nucleophiles as the key cleavage reaction.

Apart from the well‐known constituents (+)‐β‐selinene (2), (−)‐β‐elemene (4), (+)‐β‐costol (7), (−)‐caryophyllene (17), and (−)‐elemol (19) the following sesquiterpenoids have been isolated for the first time from costus root oil (Saussurea lappa CLARKE): (−)‐α‐selinene (1), (+)‐selina‐4, 11‐diene (3), (−)‐α‐trans‐bergamotene (5), (−)‐α‐costol (6), (+)‐γ‐costol (8), (−)‐elema‐1,3,11 (13)‐trien‐12‐ol (9), (−)‐α‐costal (11), (+)‐γ‐costal (12), (+)‐γ‐costal (13), (−)‐elema‐1,3,11 (13)‐trien‐12‐al (elemenal, 14), (−)‐(E)‐trans‐bergamota‐2, 12‐dien‐14‐al (15), (−)‐ar‐curcumene (16), and (−)‐caryophyllene oxide (18). Compounds 6, 8, 9, and 13 are new sesquiterpenoids. IR. and NMR. spectra of 12 sesquiterpenoids are reproduced.

SummaryThe isolation and synthesis of (cis-6-methyltetrahtydropyran-2-yl)acetic acid (la), a novel compound from civet (Viverra civetta), are reported.In the course of analysis of the volatile acids of civet') we ]identified, besides various common aliphatic carboxylic acids (saturated, unsaturated, straight chain and branched, containing 2 to 18 carbon atoms), the heterocyclic carboxylic acid la2). To the best of our knowledge, neither the natural occurrence nor the synthesis of this acid has been reported.The new compound was isolated and identified in the form of its methyl ester 2a, the constitution of which was deduced from the spectral data. The mass spectrum (molecular ion at mle 172) and the NMR. spectrum (16 protons) indicated the empirical formula C9H 1603. Jnfra-red spectroscopy confirmed the presence of a non-conjugated ester group absorbing at 1740 cm-'. The 'H-NMR. spectrum revealed the nature and the relative position of the third oxygen atom with respect to the ester function. The presence of the partial structure CH3-CH-O-CH-CH2-COOCH3was suggested by signals at 6 1.14 (d, J = 6 . 5 (m, 1 H, -0-CH-CH2COO-).The methylene protons next to the ester function appeared as the A B part of an A B X system with 6,=2.40, dB=2.58, J A B = 15 Hz, J,,=6Hz, J,,=7 Hz. Irradiation at the center of this signal resulted in a simplification of the m at 3.80, and irradiation at 3.47 chan,ged the d at 1.14 3 H, CH,-CH-O-); 3.47 (m, 1 H, CH,-CH-O--); 3.69 (s, 3 H, -COOCH,);Civet is the glandular secretion from the civet cat (Viverru civetta). Together with ambergris, castoreum and musk, it is one of the few very expensive animal perfume materials [I]. l a has a very faint sour-fatty odour.

[7].Wahrend die Verbindungen 1-3 iin sog. typischen [S]

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