Synthetic plant growth regulators. VI. The partial synthesis of optically active (4β,15α)-18-Norkaurene-15-carboxylic acids from (4β)-18-norkauren-3-one by means of a pyrrolidinium ylide rearrangement

1980 ◽  
Vol 33 (9) ◽  
pp. 2061 ◽  
Author(s):  
AL Cossey ◽  
LN Mander ◽  
JV Turner
Keyword(s):  
Carboxylic Acid ◽  
Plant Growth ◽  
Carboxylic Acids ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Sodium Borohydride ◽  
Sigmatropic Rearrangement ◽  
Optically Active ◽  
Allylic Amines ◽  
Partial Synthesis

(4β)-18-Norkaur-16-en-3-one (4a) was alternatively acetalized (ethanediol/Dowex resin) or deoxygenated (tosylhydrazine/sodium borohydride); allylic bromination (N-bromosuccinimide) of the products, followed by alkylation of pyrrolidine gave primary allylic amines which were quaternized with chloroacetonitrile. Potassium t-butoxide-induced [2,3]-sigmatropic rearrangement, followed by acidic hydrolysis and Jones oxidation, gave respectively (4β,15α)-3-oxo-18-norkaur-16-ene-15- carboxylic acid (10a) and (4β,15α)-18-norkaur-16-ene-15-carboxylic acid. Reductions of (4a) and (10a) gave, with K-Selectride, axial (3β)- alcohols and, with sodium borohydride, mainly equatorial (3α)-alcohols. Details of a related conversion of (+)-phyllocladene into (15α)- phyllocladene-15-carboxylic acid are also recorded.

Synthetic Plant Growth Regulators. IV. The Preparation of Hydroxylated Helminthosporic Acid Analogues

1979 ◽  
Vol 32 (4) ◽  
pp. 823 ◽  
Author(s):  
LN Mander ◽  
LT Palmer
Keyword(s):  
Plant Growth ◽  
Plant Growth Regulators ◽  
Lewis Acid ◽  
Growth Regulators ◽  
Sodium Borohydride ◽  
Sigmatropic Rearrangement ◽  
Hydroxyl Group ◽  
Hydroxy Ketone ◽  
Wittig Olefination ◽  
Sequential Reduction

Sequential reduction (sodium borohydride, metal-ammonia, hydrogenation) of ketone (8) gave the hydroxy ketone (9) which was converted into olefin (10) (Wittig olefination) and thence to acid (14) by means of the [2,3] sigmatropic rearrangement of ylide (12) to (13). Acid (15) was similarly prepared from alcohol (11) which was obtained by deoxygenation of ketone (9). The tetrahydrocuminic acid (16) was hydroxylated (lithium diisopropylamine, oxygen); the new hydroxyl group was protected with a dichloroacetyl function and then converted into the diazoketone. Lewis-acid-induced cyclization of (17) gave the bicyclooctanone (18a) plus its Δ3-isomer (18b), both of which were reduced and hydrolysed to hydroxy ketone (19). Wittig methylenation of (19) gave olefin (20) which was rearranged by acid to ketone (21). Both (20) and (21) were elaborated further to the acids (6) and (25), respectively, by the procedures used in the preparation of acids (14) and (15).

scholarly journals Controlling Growth of Common Carpetgrass Using Selected Plant Growth Regulators

HortScience ◽  
1998 ◽  
Vol 33 (4) ◽  
pp. 704-706 ◽  
Author(s):  
Edward W. Bush ◽  
Wayne C. Porter ◽  
Dennis P. Shepard ◽  
James N. McCrimmon
Keyword(s):  
Carboxylic Acid ◽  
Plant Growth ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Acid Ethyl Ester ◽  
Field Studies ◽  
Turf Quality ◽  
Application Rates ◽  
Cyclohexane Carboxylic Acid

Field studies were performed on established carpetgrass (Axonopus affinis Chase) in 1994 and 1995 to evaluate plant growth regulators (PGRs) and application rates. Trinexapac-ethyl (0.48 kg·ha-1) improved turf quality and reduced cumulative vegetative growth (CVG) of unmowed and mowed plots by 38% and 46%, respectively, in 1995, and suppressed seedhead height in unmowed turf by >31% 6 weeks after treatment (WAT) both years. Mefluidide (0.14 and 0.28 kg·ha-1) had little effect on carpetgrass. Sulfometuron resulted in unacceptable phytotoxicity (>20%) 2 WAT in 1994 and 18% phytotoxicity in 1995. In 1995, sulfometuron reduced mowed carpetgrass CVG 21%, seedhead number 47%, seedhead height 36%, clipping yield 24%, and reduced the number of mowings required. It also improved unmowed carpetgrass quality at 6 WAT. Sethoxydim (0.11 kg·ha-1) suppressed seedhead formation by 60% and seedhead height by 20%, and caused moderate phytotoxicity (13%) in 1995. Sethoxydim (0.22 kg·ha-1) was unacceptably phytotoxic (38%) in 1994, but only slightly phytotoxic (7%) in 1995, reduced clipping yields (>24%), and increased quality of mowed carpetgrass both years. Fluazasulfuron (0.027 and 0.054 kg·ha-1) phytotoxicity ratings were unacceptable at 2 WAT in 1994, but not in 1995. Fluazasulfuron (0.054 kg·ha-1) reduced seedhead height by 23% to 26% in both years. Early seedhead formation was suppressed >70% when applied 2 WAT in 1994, and 43% when applied 6 WAT in 1995. The effects of the chemicals varied with mowing treatment and evaluation year. Chemical names used: 4-(cyclopropyl-x-hydroxy-methylene)-3,5 dioxo-cyclohexane-carboxylic acid ethyl ester (trinexapac-ethyl); N-2,4-dimethyl-5-[[(trifluoro-methyl)sulfonyl]amino]phenyl]acetamide] (mefluidide); [methyl 2-[[[[(4,6-dimethyl-2-pyrimidinyl) amino]carbonyl] amino] sulfonyl]benzoate)] (sulfometuron); (2-[1-(ethoxyimino)butyl-5-[(2-ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one) (sethoxydim); 1-(4,6-dimethoxypyrimidin-2yl)-3-[(3-trifluoromethyl-pyridin 2-yl) sulphonyl] urea (fluazasulfuron).

Synthetic plant growth regulators. I. The synthesis of (±)-14-Norhelminthosporic acid and related compounds

1974 ◽  
Vol 27 (9) ◽  
pp. 1985 ◽  
Author(s):  
LN Mander ◽  
JV Turner ◽  
BG Coombe
Keyword(s):  
Plant Growth ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Sigmatropic Rearrangement ◽  
Ammonium Bromide ◽  
Reductive Methylation ◽  
Allylic Bromide ◽  
Related Compounds

Cuminic acid (9) was converted by reductive methylation into 1,2,3,6-tetrahydro-4-isopropyl-1- methylbenzoic acid (12). Acid-catalysed cyclization of the diazomethyl ketone (8) derived from (12), followed by hydrogenation, gave the bicyclo[3,2,l]octanone derivative (7), which was then converted through the allylic bromide mixture of (18) and (19) into the p-toluenesulphonyldithiocarbazone (21) and the allylic ammonium bromide (25). The [2,3]-sigmatropic rearrangement of the dithio- carbene derived from (21) and the ylid derived from (25) afforded the dithioester (22) and pyrrolidine (26), respectively, from which the alcohol (24), aldehydes (27) and (28), and acids (5) and (6) were prepared. Bioassay of (5), (6), (27) and (28) indicated gibberellin-like properties for all these compounds with potency comparable with that of helminthosporic acid (2).

Synthesis of optically active cyclohexanone analogs of the plant hormone abscisic acid

1990 ◽  
Vol 68 (7) ◽  
pp. 1151-1162 ◽  
Author(s):  
Nancy Lamb ◽  
Suzanne R. Abrams
Keyword(s):  
Abscisic Acid ◽  
Plant Growth ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Plant Hormone ◽  
Optically Active ◽  
Common Precursor

The abscisic acid analogs (−)-(4R,5R)-, (+)-(4S,5S)-, and (−)-(4S,5R)-4(1E,3Z)-4-(4-carboxy-3-methyl-1,3-butadienyl)-4-hydroxy-3,3,5-trimethylcyclohexanones (dihydroabscisic acids), and (−)-(4S,5R)-, (+)-(4R,5S)-, and (−)-(4R,5R)-4(Z)-4-hydroxy-4-(5-hydroxy-3-methylpent-3-en-1-ynyl)-3,3,5-trimethylcyclohexanones were synthesized from a common precursor, (−)-(6R)-2,2,6-trimethylcyclohexan-1,4-dione, which was readily prepared by the fermentation of oxoisophorone with bakers' yeast. Keywords: abscisic acid, dihydroabscisic acid, acetylenic analogs, optically active analogs, plant growth regulators.

Sign in / Sign up

Export Citation Format

Share Document